91295144640 has 168 divisors, whose sum is σ = 358876945440. Its totient is φ = 20867457024.

The previous prime is 91295144621. The next prime is 91295144641. The reversal of 91295144640 is 4644159219.

91295144640 is a `hidden beast` number, since 9 + 129 + 514 + 4 + 6 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (168).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (91295144641) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2244105 + ... + 2284424.

Almost surely, 2^91295144640 is an apocalyptic number.

91295144640 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

91295144640 is an abundant number, since it is smaller than the sum of its proper divisors (267581800800).

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

91295144640 is a wasteful number, since it uses less digits than its factorization.

91295144640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4528559 (or 4528546 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 91295144640 in words is "ninety-one billion, two hundred ninety-five million, one hundred forty-four thousand, six hundred forty".