20813960 has 16 divisors (see below), whose sum is σ = 46831500. Its totient is φ = 8325568.

The previous prime is 20813957. The next prime is 20813963. The reversal of 20813960 is 6931802.

It is an interprime number because it is at equal distance from previous prime (20813957) and next prime (20813963).

It can be written as a sum of positive squares in 2 ways, for example, as 20811844 + 2116 = 4562^2 + 46^2 .

It is not an unprimeable number, because it can be changed into a prime (20813963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 260135 + ... + 260214.

Almost surely, 2^20813960 is an apocalyptic number.

20813960 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20813960 is an abundant number, since it is smaller than the sum of its proper divisors (26017540).

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

20813960 is a wasteful number, since it uses less digits than its factorization.

20813960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 520360 (or 520356 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 20813960 is about 4562.2319099318. The cubic root of 20813960 is about 275.0752851729.

The spelling of 20813960 in words is "twenty million, eight hundred thirteen thousand, nine hundred sixty".