20990120 has 32 divisors (see below), whose sum is σ = 48123720. Its totient is φ = 8236800.

The previous prime is 20990111. The next prime is 20990143. The reversal of 20990120 is 2109902.

It can be written as a sum of positive squares in 4 ways, for example, as 20921476 + 68644 = 4574^2 + 262^2 .

It is a super-2 number, since 2×20990120² = 881170275228800, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2831 + ... + 7070.

Almost surely, 2^20990120 is an apocalyptic number.

20990120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20990120 is an abundant number, since it is smaller than the sum of its proper divisors (27133600).

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

20990120 is a wasteful number, since it uses less digits than its factorization.

20990120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9965 (or 9961 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 20990120 is about 4581.4975717553. The cubic root of 20990120 is about 275.8491439131.

The spelling of 20990120 in words is "twenty million, nine hundred ninety thousand, one hundred twenty".