90640917 has 8 divisors (see below), whose sum is σ = 134282880. Its totient is φ = 60427260.

The previous prime is 90640871. The next prime is 90640939. The reversal of 90640917 is 71904609.

90640917 is a `hidden beast` number, since 9 + 0 + 640 + 9 + 1 + 7 = 666.

It is not a de Polignac number, because 90640917 - 2⁶ = 90640853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90640117) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1678509 + ... + 1678562.

It is an arithmetic number, because the mean of its divisors is an integer number (16785360).

Almost surely, 2^90640917 is an apocalyptic number.

It is an amenable number.

90640917 is a deficient number, since it is larger than the sum of its proper divisors (43641963).

90640917 is a wasteful number, since it uses less digits than its factorization.

90640917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3357080 (or 3357074 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 36.

The square root of 90640917 is about 9520.5523474219. The cubic root of 90640917 is about 449.2017403518.

The spelling of 90640917 in words is "ninety million, six hundred forty thousand, nine hundred seventeen".