19930805664 has 288 divisors, whose sum is σ = 69283662336. Its totient is φ = 4951457280.

The previous prime is 19930805663. The next prime is 19930805677. The reversal of 19930805664 is 46650803991.

It is a super-2 number, since 2×19930805664² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19930805663) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1181739 + ... + 1198485.

It is an arithmetic number, because the mean of its divisors is an integer number (240568272).

Almost surely, 2^19930805664 is an apocalyptic number.

19930805664 is a gapful number since it is divisible by the number (14) 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 19930805664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34641831168).

19930805664 is an abundant number, since it is smaller than the sum of its proper divisors (49352856672).

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

19930805664 is a wasteful number, since it uses less digits than its factorization.

19930805664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16808 (or 16793 counting only the distinct ones).

The product of its (nonzero) digits is 1399680, while the sum is 51.

The spelling of 19930805664 in words is "nineteen billion, nine hundred thirty million, eight hundred five thousand, six hundred sixty-four".