191631920255 has 8 divisors (see below), whose sum is σ = 235306172112. Its totient is φ = 149740291008.

The previous prime is 191631920251. The next prime is 191631920287. The reversal of 191631920255 is 552029136191.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 191631920255 - 2² = 191631920251 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 (191631920251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 445655414 + ... + 445655843.

It is an arithmetic number, because the mean of its divisors is an integer number (29413271514).

Almost surely, 2^191631920255 is an apocalyptic number.

191631920255 is a deficient number, since it is larger than the sum of its proper divisors (43674251857).

191631920255 is an equidigital number, since it uses as much as digits as its factorization.

191631920255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 891311305.

The product of its (nonzero) digits is 145800, while the sum is 44.

The spelling of 191631920255 in words is "one hundred ninety-one billion, six hundred thirty-one million, nine hundred twenty thousand, two hundred fifty-five".