97521640 has 64 divisors (see below), whose sum is σ = 227525760. Its totient is φ = 37589760.

The previous prime is 97521637. The next prime is 97521647. The reversal of 97521640 is 4612579.

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 97521596 and 97521605.

It is not an unprimeable number, because it can be changed into a prime (97521647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 193629 + ... + 194131.

It is an arithmetic number, because the mean of its divisors is an integer number (3555090).

Almost surely, 2^97521640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 97521640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113762880).

97521640 is an abundant number, since it is smaller than the sum of its proper divisors (130004120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

97521640 is a wasteful number, since it uses less digits than its factorization.

97521640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 682 (or 678 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 97521640 is about 9875.3045522657. The cubic root of 97521640 is about 460.2922528463.

The spelling of 97521640 in words is "ninety-seven million, five hundred twenty-one thousand, six hundred forty".