19664249690 has 64 divisors (see below), whose sum is σ = 39484972800. Its totient is φ = 7007210496.

The previous prime is 19664249651. The next prime is 19664249699. The reversal of 19664249690 is 9694246691.

It is a super-2 number, since 2×19664249690² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19664249699) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5285651 + ... + 5289369.

It is an arithmetic number, because the mean of its divisors is an integer number (616952700).

Almost surely, 2^19664249690 is an apocalyptic number.

19664249690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19664249690 is an abundant number, since it is smaller than the sum of its proper divisors (19820723110).

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

19664249690 is a wasteful number, since it uses less digits than its factorization.

19664249690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5399.

The product of its (nonzero) digits is 5038848, while the sum is 56.

The spelling of 19664249690 in words is "nineteen billion, six hundred sixty-four million, two hundred forty-nine thousand, six hundred ninety".