19642493 has 4 divisors (see below), whose sum is σ = 21153468. Its totient is φ = 18131520.

The previous prime is 19642477. The next prime is 19642501. The reversal of 19642493 is 39424691.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 39424691 = 23 ⋅1714117.

It can be written as a sum of positive squares in 2 ways, for example, as 7546009 + 12096484 = 2747^2 + 3478^2 .

It is a cyclic number.

It is not a de Polignac number, because 19642493 - 2⁴ = 19642477 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19642453) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 755468 + ... + 755493.

It is an arithmetic number, because the mean of its divisors is an integer number (5288367).

Almost surely, 2^19642493 is an apocalyptic number.

19642493 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

19642493 is a deficient number, since it is larger than the sum of its proper divisors (1510975).

19642493 is a wasteful number, since it uses less digits than its factorization.

19642493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1510974.

The product of its digits is 46656, while the sum is 38.

The square root of 19642493 is about 4431.9852210945. The cubic root of 19642493 is about 269.8146556050.

The spelling of 19642493 in words is "nineteen million, six hundred forty-two thousand, four hundred ninety-three".