90171639 has 6 divisors (see below), whose sum is σ = 130247936. Its totient is φ = 60114420.

The previous prime is 90171607. The next prime is 90171649. The reversal of 90171639 is 93617109.

90171639 is a `hidden beast` number, since 9 + 0 + 17 + 1 + 639 = 666.

It is not a de Polignac number, because 90171639 - 2⁵ = 90171607 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 (90171649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5009527 + ... + 5009544.

Almost surely, 2^90171639 is an apocalyptic number.

90171639 is a deficient number, since it is larger than the sum of its proper divisors (40076297).

90171639 is a wasteful number, since it uses less digits than its factorization.

90171639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10019077 (or 10019074 counting only the distinct ones).

The product of its (nonzero) digits is 10206, while the sum is 36.

The square root of 90171639 is about 9495.8748412139. The cubic root of 90171639 is about 448.4251766470.

The spelling of 90171639 in words is "ninety million, one hundred seventy-one thousand, six hundred thirty-nine".