990617920 has 28 divisors (see below), whose sum is σ = 2358909684. Its totient is φ = 396247040.

The previous prime is 990617917. The next prime is 990617921. The reversal of 990617920 is 29716099.

It can be written as a sum of positive squares in 2 ways, for example, as 774174976 + 216442944 = 27824^2 + 14712^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990617921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1547521 + ... + 1548160.

Almost surely, 2^990617920 is an apocalyptic number.

It is an amenable number.

990617920 is an abundant number, since it is smaller than the sum of its proper divisors (1368291764).

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

990617920 is a wasteful number, since it uses less digits than its factorization.

990617920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3095698 (or 3095688 counting only the distinct ones).

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 990617920 is about 31474.0833067462. The cubic root of 990617920 is about 996.8628083204.

The spelling of 990617920 in words is "nine hundred ninety million, six hundred seventeen thousand, nine hundred twenty".