20479920 has 40 divisors (see below), whose sum is σ = 63488496. Its totient is φ = 5461248.

The previous prime is 20479919. The next prime is 20479937. The reversal of 20479920 is 2997402.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42427 + ... + 42906.

Almost surely, 2^20479920 is an apocalyptic number.

20479920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20479920 is an abundant number, since it is smaller than the sum of its proper divisors (43008576).

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

20479920 is a wasteful number, since it uses less digits than its factorization.

20479920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85349 (or 85343 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 20479920 is about 4525.4745607505. The cubic root of 20479920 is about 273.5957952228.

The spelling of 20479920 in words is "twenty million, four hundred seventy-nine thousand, nine hundred twenty".