90008640 has 84 divisors (see below), whose sum is σ = 309602124. Its totient is φ = 24001536.

The previous prime is 90008627. The next prime is 90008641. The reversal of 90008640 is 4680009.

It can be written as a sum of positive squares in 2 ways, for example, as 43877376 + 46131264 = 6624^2 + 6792^2 .

It is not an unprimeable number, because it can be changed into a prime (90008641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12747 + ... + 18506.

Almost surely, 2^90008640 is an apocalyptic number.

90008640 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

90008640 is an abundant number, since it is smaller than the sum of its proper divisors (219593484).

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

90008640 is a wasteful number, since it uses less digits than its factorization.

90008640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31276 (or 31263 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 90008640 is about 9487.2883375599. The cubic root of 90008640 is about 448.1548146920.

Adding to 90008640 its reverse (4680009), we get a palindrome (94688649).

The spelling of 90008640 in words is "ninety million, eight thousand, six hundred forty".