91979100 has 54 divisors (see below), whose sum is σ = 288306200. Its totient is φ = 24527520.

The previous prime is 91979087. The next prime is 91979101. The reversal of 91979100 is 197919.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91979101) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 50200 + ... + 51999.

Almost surely, 2^91979100 is an apocalyptic number.

91979100 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

91979100 is an abundant number, since it is smaller than the sum of its proper divisors (196327100).

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

91979100 is a wasteful number, since it uses less digits than its factorization.

91979100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102219 (or 102209 counting only the distinct ones).

The product of its (nonzero) digits is 5103, while the sum is 36.

The square root of 91979100 is about 9590.5734969292. The cubic root of 91979100 is about 451.4015561503.

The spelling of 91979100 in words is "ninety-one million, nine hundred seventy-nine thousand, one hundred".