20978080 has 24 divisors (see below), whose sum is σ = 49561092. Its totient is φ = 8391168.

The previous prime is 20978077. The next prime is 20978117. The reversal of 20978080 is 8087902.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 19820304 + 1157776 = 4452^2 + 1076^2 .

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 3 ways as a sum of consecutive naturals, for example, 65397 + ... + 65716.

Almost surely, 2^20978080 is an apocalyptic number.

20978080 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20978080 is an abundant number, since it is smaller than the sum of its proper divisors (28583012).

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

20978080 is a wasteful number, since it uses less digits than its factorization.

20978080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131128 (or 131120 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 20978080 is about 4580.1834024414. The cubic root of 20978080 is about 275.7963911749.

The spelling of 20978080 in words is "twenty million, nine hundred seventy-eight thousand, eighty".