20279808 has 120 divisors (see below), whose sum is σ = 61069008. Its totient is φ = 6718464.

The previous prime is 20279803. The next prime is 20279839. The reversal of 20279808 is 80897202.

It is a super-2 number, since 2×20279808² = 822541225033728, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (20279803) 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, 124335 + ... + 124497.

Almost surely, 2^20279808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20279808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30534504).

20279808 is an abundant number, since it is smaller than the sum of its proper divisors (40789200).

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

20279808 is an frugal number, since it uses more digits than its factorization.

20279808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196 (or 168 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 20279808 is about 4503.3107820802. The cubic root of 20279808 is about 272.7017634323.

The spelling of 20279808 in words is "twenty million, two hundred seventy-nine thousand, eight hundred eight".