990135688 has 32 divisors (see below), whose sum is σ = 1921766400. Its totient is φ = 477876672.

The previous prime is 990135659. The next prime is 990135689. The reversal of 990135688 is 886531099.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (990135689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24423 + ... + 50761.

It is an arithmetic number, because the mean of its divisors is an integer number (60055200).

Almost surely, 2^990135688 is an apocalyptic number.

It is an amenable number.

990135688 is a deficient number, since it is larger than the sum of its proper divisors (931630712).

990135688 is a wasteful number, since it uses less digits than its factorization.

990135688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26509 (or 26505 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 49.

The square root of 990135688 is about 31466.4215950909. The cubic root of 990135688 is about 996.7010247300.

The spelling of 990135688 in words is "nine hundred ninety million, one hundred thirty-five thousand, six hundred eighty-eight".