97521639 has 16 divisors (see below), whose sum is σ = 137894400. Its totient is φ = 61093760.

The previous prime is 97521637. The next prime is 97521647. The reversal of 97521639 is 93612579.

It is a cyclic number.

It is not a de Polignac number, because 97521639 - 2¹ = 97521637 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 97521639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (97521637) 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, 45412 + ... + 47510.

It is an arithmetic number, because the mean of its divisors is an integer number (8618400).

Almost surely, 2^97521639 is an apocalyptic number.

97521639 is a deficient number, since it is larger than the sum of its proper divisors (40372761).

97521639 is a wasteful number, since it uses less digits than its factorization.

97521639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3030.

The product of its digits is 102060, while the sum is 42.

The square root of 97521639 is about 9875.3045016344. The cubic root of 97521639 is about 460.2922512730.

The spelling of 97521639 in words is "ninety-seven million, five hundred twenty-one thousand, six hundred thirty-nine".