99561870 has 24 divisors (see below), whose sum is σ = 258861096. Its totient is φ = 26549808.

The previous prime is 99561823. The next prime is 99561887. The reversal of 99561870 is 7816599.

99561870 is a `hidden beast` number, since 9 + 9 + 561 + 87 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 553032 + ... + 553211.

It is an arithmetic number, because the mean of its divisors is an integer number (10785879).

Almost surely, 2^99561870 is an apocalyptic number.

99561870 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

99561870 is an abundant number, since it is smaller than the sum of its proper divisors (159299226).

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

99561870 is a wasteful number, since it uses less digits than its factorization.

99561870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1106256 (or 1106253 counting only the distinct ones).

The product of its (nonzero) digits is 136080, while the sum is 45.

The square root of 99561870 is about 9978.0694525544. The cubic root of 99561870 is about 463.4800178508.

The spelling of 99561870 in words is "ninety-nine million, five hundred sixty-one thousand, eight hundred seventy".