99995721 has 24 divisors (see below), whose sum is σ = 155552544. Its totient is φ = 56972160.

The previous prime is 99995711. The next prime is 99995723. The reversal of 99995721 is 12759999.

It is not a de Polignac number, because 99995721 - 2⁹ = 99995209 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (99995723) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 62866 + ... + 64436.

It is an arithmetic number, because the mean of its divisors is an integer number (6481356).

Almost surely, 2^99995721 is an apocalyptic number.

It is an amenable number.

99995721 is a deficient number, since it is larger than the sum of its proper divisors (55556823).

99995721 is a wasteful number, since it uses less digits than its factorization.

99995721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2021 (or 2014 counting only the distinct ones).

The product of its digits is 459270, while the sum is 51.

The square root of 99995721 is about 9999.7860477112. The cubic root of 99995721 is about 464.1522628140.

The spelling of 99995721 in words is "ninety-nine million, nine hundred ninety-five thousand, seven hundred twenty-one".