99979992 has 144 divisors (see below), whose sum is σ = 333716760. Its totient is φ = 26869248.

The previous prime is 99979981. The next prime is 99979993. The reversal of 99979992 is 29997999.

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

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99979993) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 59143 + ... + 60809.

Almost surely, 2^99979992 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 99979992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (166858380).

99979992 is an abundant number, since it is smaller than the sum of its proper divisors (233736768).

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

99979992 is a wasteful number, since it uses less digits than its factorization.

99979992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1710 (or 1696 counting only the distinct ones).

The product of its digits is 7440174, while the sum is 63.

The square root of 99979992 is about 9998.9995499550. Note that the first 3 decimals coincide. The cubic root of 99979992 is about 464.1279249933.

The spelling of 99979992 in words is "ninety-nine million, nine hundred seventy-nine thousand, nine hundred ninety-two".