97911921 has 16 divisors (see below), whose sum is σ = 137931840. Its totient is φ = 61608960.

The previous prime is 97911899. The next prime is 97911929. The reversal of 97911921 is 12911979.

It is not a de Polignac number, because 97911921 - 2¹⁵ = 97879153 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 97911921.

It is not an unprimeable number, because it can be changed into a prime (97911929) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12961 + ... + 19073.

It is an arithmetic number, because the mean of its divisors is an integer number (8620740).

Almost surely, 2^97911921 is an apocalyptic number.

It is an amenable number.

97911921 is a deficient number, since it is larger than the sum of its proper divisors (40019919).

97911921 is a wasteful number, since it uses less digits than its factorization.

97911921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6416.

The product of its digits is 10206, while the sum is 39.

The square root of 97911921 is about 9895.0452752880. The cubic root of 97911921 is about 460.9054644655.

The spelling of 97911921 in words is "ninety-seven million, nine hundred eleven thousand, nine hundred twenty-one".