19664823040 has 36 divisors (see below), whose sum is σ = 47103399504. Its totient is φ = 7865928704.

The previous prime is 19664823029. The next prime is 19664823047. The reversal of 19664823040 is 4032846691.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (19664823047) 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, 7680292 + ... + 7682851.

It is an arithmetic number, because the mean of its divisors is an integer number (1308427764).

Almost surely, 2^19664823040 is an apocalyptic number.

19664823040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19664823040 is an abundant number, since it is smaller than the sum of its proper divisors (27438576464).

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

19664823040 is an equidigital number, since it uses as much as digits as its factorization.

19664823040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15363164 (or 15363150 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 43.

The spelling of 19664823040 in words is "nineteen billion, six hundred sixty-four million, eight hundred twenty-three thousand, forty".