15961393461591 has 48 divisors (see below), whose sum is σ = 23638742985312. Its totient is φ = 10372137292800.

The previous prime is 15961393461527. The next prime is 15961393461593. The reversal of 15961393461591 is 19516439316951.

15961393461591 is a `hidden beast` number, since 1 + 5 + 9 + 6 + 1 + 3 + 9 + 3 + 4 + 615 + 9 + 1 = 666.

It is not a de Polignac number, because 15961393461591 - 2⁶ = 15961393461527 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15961393461593) 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, 2966247721 + ... + 2966253101.

It is an arithmetic number, because the mean of its divisors is an integer number (492473812194).

Almost surely, 2^{15961393461591} is an apocalyptic number.

15961393461591 is a deficient number, since it is larger than the sum of its proper divisors (7677349523721).

15961393461591 is a wasteful number, since it uses less digits than its factorization.

15961393461591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11104 (or 11101 counting only the distinct ones).

The product of its digits is 23619600, while the sum is 63.

The spelling of 15961393461591 in words is "fifteen trillion, nine hundred sixty-one billion, three hundred ninety-three million, four hundred sixty-one thousand, five hundred ninety-one".