91977670449 has 32 divisors (see below), whose sum is σ = 155988698880. Its totient is φ = 52471152000.

The previous prime is 91977670441. The next prime is 91977670457. The reversal of 91977670449 is 94407677919.

It is an interprime number because it is at equal distance from previous prime (91977670441) and next prime (91977670457).

It is not a de Polignac number, because 91977670449 - 2³ = 91977670441 is a prime.

It is a super-2 number, since 2×91977670449² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (91977670441) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 291282 + ... + 518459.

It is an arithmetic number, because the mean of its divisors is an integer number (4874646840).

Almost surely, 2^91977670449 is an apocalyptic number.

It is an amenable number.

91977670449 is a deficient number, since it is larger than the sum of its proper divisors (64011028431).

91977670449 is a wasteful number, since it uses less digits than its factorization.

91977670449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810358 (or 810352 counting only the distinct ones).

The product of its (nonzero) digits is 24004512, while the sum is 63.

The spelling of 91977670449 in words is "ninety-one billion, nine hundred seventy-seven million, six hundred seventy thousand, four hundred forty-nine".