• 19602 is the least such that

= rev() - /sod(), where rev() denotes the digital reversal of and sod() is the sum of digits of . The next such is 296703, while a larger example is 392040039204.

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19602 has 30 divisors (see below), whose sum is σ = 48279. Its totient is φ = 5940.

The previous prime is 19597. The next prime is 19603. The reversal of 19602 is 20691.

It can be written as a sum of positive squares in only one way, i.e., 9801 + 9801 = 99^2 + 99^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=99.

It is a Smith number, since the sum of its digits (18) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nialpdrome in base 3.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (19603) by changing a digit.

19602 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 1777 + ... + 1787.

2¹⁹⁶⁰² is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19602

19602 is an abundant number, since it is smaller than the sum of its proper divisors (28677).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19602 is a wasteful number, since it uses less digits than its factorization.

19602 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36 (or 16 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 19602 is about 140.0071426749. The cubic root of 19602 is about 26.9629120412.

Multiplying 19602 by its sum of digits (18), we get a square (352836 = 594²).

19602 divided by its sum of digits (18) gives a square (1089 = 33²).

Subtracting 19602 from its reverse (20691), we obtain a square (1089 = 33²).

The spelling of 19602 in words is "nineteen thousand, six hundred two".