15974013955991 has 80 divisors (see below), whose sum is σ = 19931976355584. Its totient is φ = 12540382073856.

The previous prime is 15974013955981. The next prime is 15974013956009. The reversal of 15974013955991 is 19955931047951.

It is a de Polignac number, because none of the positive numbers 2^k-15974013955991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15974013955961) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 23735533031 + ... + 23735533703.

Almost surely, 2^{15974013955991} is an apocalyptic number.

15974013955991 is a deficient number, since it is larger than the sum of its proper divisors (3957962399593).

15974013955991 is an frugal number, since it uses more digits than its factorization.

15974013955991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1482 (or 1443 counting only the distinct ones).

The product of its (nonzero) digits is 68890500, while the sum is 68.

The spelling of 15974013955991 in words is "fifteen trillion, nine hundred seventy-four billion, thirteen million, nine hundred fifty-five thousand, nine hundred ninety-one".