91271656980 has 720 divisors, whose sum is σ = 357094657920. Its totient is φ = 19050204672.

The previous prime is 91271656937. The next prime is 91271656991. The reversal of 91271656980 is 8965617219.

91271656980 is a `hidden beast` number, since 9 + 1 + 2 + 71 + 6 + 569 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 853006087 + ... + 853006193.

Almost surely, 2^91271656980 is an apocalyptic number.

91271656980 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91271656980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (178547328960).

91271656980 is an abundant number, since it is smaller than the sum of its proper divisors (265823000940).

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

91271656980 is a wasteful number, since it uses less digits than its factorization.

91271656980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298 (or 180 counting only the distinct ones).

The product of its (nonzero) digits is 1632960, while the sum is 54.

The spelling of 91271656980 in words is "ninety-one billion, two hundred seventy-one million, six hundred fifty-six thousand, nine hundred eighty".