99571921 has 8 divisors (see below), whose sum is σ = 103048704. Its totient is φ = 96136560.

The previous prime is 99571883. The next prime is 99571931. The reversal of 99571921 is 12917599.

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 99571921 - 2¹⁷ = 99440849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99571931) 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, 5425 + ... + 15118.

It is an arithmetic number, because the mean of its divisors is an integer number (12881088).

Almost surely, 2^99571921 is an apocalyptic number.

It is an amenable number.

99571921 is a deficient number, since it is larger than the sum of its proper divisors (3476783).

99571921 is a wasteful number, since it uses less digits than its factorization.

99571921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20711.

The product of its digits is 51030, while the sum is 43.

The square root of 99571921 is about 9978.5730943858. The cubic root of 99571921 is about 463.4956137843.

The spelling of 99571921 in words is "ninety-nine million, five hundred seventy-one thousand, nine hundred twenty-one".