11571657220 has 24 divisors (see below), whose sum is σ = 24397305408. Its totient is φ = 4610220000.

The previous prime is 11571657199. The next prime is 11571657271. The reversal of 11571657220 is 2275617511.

It is a self number, because there is not a number n which added to its sum of digits gives 11571657220.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1147536 + ... + 1157575.

It is an arithmetic number, because the mean of its divisors is an integer number (1016554392).

Almost surely, 2^11571657220 is an apocalyptic number.

11571657220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11571657220 is an abundant number, since it is smaller than the sum of its proper divisors (12825648188).

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

11571657220 is a wasteful number, since it uses less digits than its factorization.

11571657220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2305371 (or 2305369 counting only the distinct ones).

The product of its (nonzero) digits is 29400, while the sum is 37.

The spelling of 11571657220 in words is "eleven billion, five hundred seventy-one million, six hundred fifty-seven thousand, two hundred twenty".