191201972256 has 72 divisors (see below), whose sum is σ = 563868802224. Its totient is φ = 63733988160.

The previous prime is 191201972233. The next prime is 191201972261. The reversal of 191201972256 is 652279102191.

191201972256 is a `hidden beast` number, since 191 + 20 + 197 + 2 + 256 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12286590 + ... + 12302141.

It is an arithmetic number, because the mean of its divisors is an integer number (7831511142).

Almost surely, 2^191201972256 is an apocalyptic number.

191201972256 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

191201972256 is an abundant number, since it is smaller than the sum of its proper divisors (372666829968).

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

191201972256 is an equidigital number, since it uses as much as digits as its factorization.

191201972256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24588756 (or 24588736 counting only the distinct ones).

The product of its (nonzero) digits is 136080, while the sum is 45.

The spelling of 191201972256 in words is "one hundred ninety-one billion, two hundred one million, nine hundred seventy-two thousand, two hundred fifty-six".