97528120021 has 4 divisors (see below), whose sum is σ = 97741529932. Its totient is φ = 97314710112.

The previous prime is 97528120007. The next prime is 97528120037. The reversal of 97528120021 is 12002182579.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 37341311121 + 60186808900 = 193239^2 + 245330^2 .

It is a cyclic number.

It is not a de Polignac number, because 97528120021 - 2¹⁹ = 97527595733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (97528120621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106704270 + ... + 106705183.

It is an arithmetic number, because the mean of its divisors is an integer number (24435382483).

Almost surely, 2^97528120021 is an apocalyptic number.

It is an amenable number.

97528120021 is a deficient number, since it is larger than the sum of its proper divisors (213409911).

97528120021 is a wasteful number, since it uses less digits than its factorization.

97528120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213409910.

The product of its (nonzero) digits is 20160, while the sum is 37.

The spelling of 97528120021 in words is "ninety-seven billion, five hundred twenty-eight million, one hundred twenty thousand, twenty-one".