99213521 has 8 divisors (see below), whose sum is σ = 108833088. Its totient is φ = 89694000.

The previous prime is 99213487. The next prime is 99213557. The reversal of 99213521 is 12531299.

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

It is not a de Polignac number, because 99213521 - 2²² = 95019217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99213571) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22925 + ... + 26906.

It is an arithmetic number, because the mean of its divisors is an integer number (13604136).

Almost surely, 2^99213521 is an apocalyptic number.

It is an amenable number.

99213521 is a deficient number, since it is larger than the sum of its proper divisors (9619567).

99213521 is a wasteful number, since it uses less digits than its factorization.

99213521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50023.

The product of its digits is 4860, while the sum is 32.

The square root of 99213521 is about 9960.5984257975. The cubic root of 99213521 is about 462.9388419111.

The spelling of 99213521 in words is "ninety-nine million, two hundred thirteen thousand, five hundred twenty-one".