97520721 has 16 divisors (see below), whose sum is σ = 138096000. Its totient is φ = 61003008.

The previous prime is 97520677. The next prime is 97520729. The reversal of 97520721 is 12702579.

It is not a de Polignac number, because 97520721 - 2¹⁵ = 97487953 is a prime.

It is not an unprimeable number, because it can be changed into a prime (97520729) 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, 15060 + ... + 20538.

It is an arithmetic number, because the mean of its divisors is an integer number (8631000).

Almost surely, 2^97520721 is an apocalyptic number.

It is an amenable number.

97520721 is a deficient number, since it is larger than the sum of its proper divisors (40575279).

97520721 is a wasteful number, since it uses less digits than its factorization.

97520721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5848.

The product of its (nonzero) digits is 8820, while the sum is 33.

The square root of 97520721 is about 9875.2580219456. The cubic root of 97520721 is about 460.2908069795.

The spelling of 97520721 in words is "ninety-seven million, five hundred twenty thousand, seven hundred twenty-one".