20561575260 has 48 divisors (see below), whose sum is σ = 57669597216. Its totient is φ = 5473830912.

The previous prime is 20561575219. The next prime is 20561575271. The reversal of 20561575260 is 6257516502.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 253369 + ... + 324528.

It is an arithmetic number, because the mean of its divisors is an integer number (1201449942).

Almost surely, 2^20561575260 is an apocalyptic number.

20561575260 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20561575260 is an abundant number, since it is smaller than the sum of its proper divisors (37108021956).

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

20561575260 is a wasteful number, since it uses less digits than its factorization.

20561575260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 578502 (or 578500 counting only the distinct ones).

The product of its (nonzero) digits is 126000, while the sum is 39.

It can be divided in two parts, 205615 and 75260, that added together give a triangular number (280875 = T₇₄₉).

The spelling of 20561575260 in words is "twenty billion, five hundred sixty-one million, five hundred seventy-five thousand, two hundred sixty".