99624721 has 4 divisors (see below), whose sum is σ = 113856832. Its totient is φ = 85392612.

The previous prime is 99624713. The next prime is 99624727. The reversal of 99624721 is 12742699.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 99624721 - 2³ = 99624713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99624727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7116045 + ... + 7116058.

It is an arithmetic number, because the mean of its divisors is an integer number (28464208).

Almost surely, 2^99624721 is an apocalyptic number.

It is an amenable number.

99624721 is a deficient number, since it is larger than the sum of its proper divisors (14232111).

99624721 is a wasteful number, since it uses less digits than its factorization.

99624721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14232110.

The product of its digits is 54432, while the sum is 40.

The square root of 99624721 is about 9981.2184125987. The cubic root of 99624721 is about 463.5775252434.

The spelling of 99624721 in words is "ninety-nine million, six hundred twenty-four thousand, seven hundred twenty-one".