99511921 has 8 divisors (see below), whose sum is σ = 101128104. Its totient is φ = 97902720.

The previous prime is 99511913. The next prime is 99511943. The reversal of 99511921 is 12911599.

It can be written as a sum of positive squares in 4 ways, for example, as 2686321 + 96825600 = 1639^2 + 9840^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 99511921 - 2³ = 99511913 is a prime.

It is a super-2 number, since 2×99511921² = 19805244842220482, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99511021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32175 + ... + 35131.

It is an arithmetic number, because the mean of its divisors is an integer number (12641013).

Almost surely, 2^99511921 is an apocalyptic number.

It is an amenable number.

99511921 is a deficient number, since it is larger than the sum of its proper divisors (1616183).

99511921 is a wasteful number, since it uses less digits than its factorization.

99511921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3491.

The product of its digits is 7290, while the sum is 37.

The square root of 99511921 is about 9975.5661994696. The cubic root of 99511921 is about 463.4024974242.

The spelling of 99511921 in words is "ninety-nine million, five hundred eleven thousand, nine hundred twenty-one".