90666520893 has 24 divisors (see below), whose sum is σ = 141073529688. Its totient is φ = 55780255872.

The previous prime is 90666520891. The next prime is 90666520969. The reversal of 90666520893 is 39802566609.

It can be written as a sum of positive squares in 4 ways, for example, as 5006694564 + 85659826329 = 70758^2 + 292677^2 .

It is not a de Polignac number, because 90666520893 - 2¹ = 90666520891 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90666520891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 359371 + ... + 557207.

It is an arithmetic number, because the mean of its divisors is an integer number (5878063737).

Almost surely, 2^90666520893 is an apocalyptic number.

It is an amenable number.

90666520893 is a deficient number, since it is larger than the sum of its proper divisors (50407008795).

90666520893 is a wasteful number, since it uses less digits than its factorization.

90666520893 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201773 (or 201770 counting only the distinct ones).

The product of its (nonzero) digits is 4199040, while the sum is 54.

The spelling of 90666520893 in words is "ninety billion, six hundred sixty-six million, five hundred twenty thousand, eight hundred ninety-three".