99900072 has 24 divisors (see below), whose sum is σ = 270562890. Its totient is φ = 33300000.

The previous prime is 99900029. The next prime is 99900077. The reversal of 99900072 is 27000999.

It can be written as a sum of positive squares in only one way, i.e., 64545156 + 35354916 = 8034^2 + 5946^2 .

It is a tau number, because it is divible by the number of its divisors (24).

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

It is not an unprimeable number, because it can be changed into a prime (99900077) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 693679 + ... + 693822.

Almost surely, 2^99900072 is an apocalyptic number.

It is an amenable number.

99900072 is an abundant number, since it is smaller than the sum of its proper divisors (170662818).

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

99900072 is a wasteful number, since it uses less digits than its factorization.

99900072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1387513 (or 1387506 counting only the distinct ones).

The product of its (nonzero) digits is 10206, while the sum is 36.

The square root of 99900072 is about 9995.0023511753. The cubic root of 99900072 is about 464.0042236040.

The spelling of 99900072 in words is "ninety-nine million, nine hundred thousand, seventy-two".