99900840 has 128 divisors (see below), whose sum is σ = 341832960. Its totient is φ = 23138304.

The previous prime is 99900797. The next prime is 99900863. The reversal of 99900840 is 4800999.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24637 + ... + 28403.

It is an arithmetic number, because the mean of its divisors is an integer number (2670570).

Almost surely, 2^99900840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 99900840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (170916480).

99900840 is an abundant number, since it is smaller than the sum of its proper divisors (241932120).

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

99900840 is a wasteful number, since it uses less digits than its factorization.

99900840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3811 (or 3807 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 99900840 is about 9995.0407703020. The cubic root of 99900840 is about 464.0054126400.

The spelling of 99900840 in words is "ninety-nine million, nine hundred thousand, eight hundred forty".