21136584420 has 96 divisors (see below), whose sum is σ = 75152313600. Its totient is φ = 4831218432.

The previous prime is 21136584397. The next prime is 21136584433. The reversal of 21136584420 is 2448563112.

It is a happy number.

21136584420 is a `hidden beast` number, since 2 + 1 + 1 + 36 + 584 + 42 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2792065 + ... + 2799624.

It is an arithmetic number, because the mean of its divisors is an integer number (782836600).

Almost surely, 2^21136584420 is an apocalyptic number.

21136584420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21136584420 is an abundant number, since it is smaller than the sum of its proper divisors (54015729180).

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

21136584420 is a wasteful number, since it uses less digits than its factorization.

21136584420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5591714 (or 5591706 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The spelling of 21136584420 in words is "twenty-one billion, one hundred thirty-six million, five hundred eighty-four thousand, four hundred twenty".