19655904690 has 40 divisors (see below), whose sum is σ = 52852545900. Its totient is φ = 5241574368.

The previous prime is 19655904661. The next prime is 19655904761. The reversal of 19655904690 is 9640955691.

19655904690 is a `hidden beast` number, since 1 + 9 + 6 + 5 + 590 + 46 + 9 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 16215730281 + 3440174409 = 127341^2 + 58653^2 .

It is a super-2 number, since 2×19655904690² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 12132465 + ... + 12134084.

Almost surely, 2^19655904690 is an apocalyptic number.

19655904690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19655904690 is an abundant number, since it is smaller than the sum of its proper divisors (33196641210).

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

19655904690 is a wasteful number, since it uses less digits than its factorization.

19655904690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24266568 (or 24266559 counting only the distinct ones).

The product of its (nonzero) digits is 2624400, while the sum is 54.

The spelling of 19655904690 in words is "nineteen billion, six hundred fifty-five million, nine hundred four thousand, six hundred ninety".