11971511571 has 16 divisors (see below), whose sum is σ = 16929216000. Its totient is φ = 7498977408.

The previous prime is 11971511551. The next prime is 11971511593. The reversal of 11971511571 is 17511517911.

It is not a de Polignac number, because 11971511571 - 2¹⁵ = 11971478803 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11971511551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 165391 + ... + 226488.

It is an arithmetic number, because the mean of its divisors is an integer number (1058076000).

Almost surely, 2^11971511571 is an apocalyptic number.

11971511571 is a deficient number, since it is larger than the sum of its proper divisors (4957704429).

11971511571 is a wasteful number, since it uses less digits than its factorization.

11971511571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392498.

The product of its digits is 11025, while the sum is 39.

The spelling of 11971511571 in words is "eleven billion, nine hundred seventy-one million, five hundred eleven thousand, five hundred seventy-one".