20815260 has 108 divisors (see below), whose sum is σ = 63559944. Its totient is φ = 5088960.

The previous prime is 20815247. The next prime is 20815271. The reversal of 20815260 is 6251802.

It is a hoax number, since the sum of its digits (24) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 20815260.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 671445 + ... + 671475.

It is an arithmetic number, because the mean of its divisors is an integer number (588518).

Almost surely, 2^20815260 is an apocalyptic number.

20815260 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20815260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31779972).

20815260 is an abundant number, since it is smaller than the sum of its proper divisors (42744684).

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

20815260 is a wasteful number, since it uses less digits than its factorization.

20815260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 20815260 is about 4562.3743818323. The cubic root of 20815260 is about 275.0810119451.

Multiplying 20815260 by its product of nonzero digits (960), we get a square (19982649600 = 141360²).

The spelling of 20815260 in words is "twenty million, eight hundred fifteen thousand, two hundred sixty".