19440977688 has 96 divisors (see below), whose sum is σ = 60462417600. Its totient is φ = 5581137600.

The previous prime is 19440977659. The next prime is 19440977719. The reversal of 19440977688 is 88677904491.

It is a super-2 number, since 2×19440977688² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 630918 + ... + 661013.

It is an arithmetic number, because the mean of its divisors is an integer number (629816850).

Almost surely, 2^19440977688 is an apocalyptic number.

19440977688 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

19440977688 is an abundant number, since it is smaller than the sum of its proper divisors (41021439912).

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

19440977688 is a wasteful number, since it uses less digits than its factorization.

19440977688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1291973 (or 1291966 counting only the distinct ones).

The product of its (nonzero) digits is 24385536, while the sum is 63.

The spelling of 19440977688 in words is "nineteen billion, four hundred forty million, nine hundred seventy-seven thousand, six hundred eighty-eight".