21606364260 has 72 divisors (see below), whose sum is σ = 70580797560. Its totient is φ = 5318489088.

The previous prime is 21606364259. The next prime is 21606364261. The reversal of 21606364260 is 6246360612.

21606364260 is a `hidden beast` number, since 2 + 1 + 6 + 0 + 6 + 3 + 642 + 6 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (21606364259) and next prime (21606364261).

It can be written as a sum of positive squares in 4 ways, for example, as 241864704 + 21364499556 = 15552^2 + 146166^2 .

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 (21606364261) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4614405 + ... + 4619084.

It is an arithmetic number, because the mean of its divisors is an integer number (980288855).

Almost surely, 2^21606364260 is an apocalyptic number.

21606364260 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21606364260 is an abundant number, since it is smaller than the sum of its proper divisors (48974433300).

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

21606364260 is a wasteful number, since it uses less digits than its factorization.

21606364260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9233517 (or 9233512 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The spelling of 21606364260 in words is "twenty-one billion, six hundred six million, three hundred sixty-four thousand, two hundred sixty".