19649340 has 72 divisors (see below), whose sum is σ = 60042528. Its totient is φ = 5201280.

The previous prime is 19649339. The next prime is 19649341. The reversal of 19649340 is 4394691.

19649340 is a `hidden beast` number, since 1 + 9 + 649 + 3 + 4 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (19649339) and next prime (19649341).

It is a Smith number, since the sum of its digits (36) 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 (36).

It is a junction number, because it is equal to n+sod(n) for n = 19649295 and 19649304.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19649341) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30825 + ... + 31455.

It is an arithmetic number, because the mean of its divisors is an integer number (833924).

Almost surely, 2^19649340 is an apocalyptic number.

19649340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19649340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30021264).

19649340 is an abundant number, since it is smaller than the sum of its proper divisors (40393188).

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

19649340 is a wasteful number, since it uses less digits than its factorization.

19649340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 819 (or 814 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 19649340 is about 4432.7576067274. The cubic root of 19649340 is about 269.8460027177.

The spelling of 19649340 in words is "nineteen million, six hundred forty-nine thousand, three hundred forty".