21137861304 has 256 divisors, whose sum is σ = 73709568000. Its totient is φ = 5472593280.

The previous prime is 21137861299. The next prime is 21137861317. The reversal of 21137861304 is 40316873112.

It is a happy number.

21137861304 is a `hidden beast` number, since 2 + 1 + 1 + 37 + 8 + 613 + 0 + 4 = 666.

It is a super-3 number, since 3×21137861304³ (a number of 32 digits) contains 333 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 644749 + ... + 676739.

It is an arithmetic number, because the mean of its divisors is an integer number (287928000).

Almost surely, 2^21137861304 is an apocalyptic number.

21137861304 is a gapful number since it is divisible by the number (24) 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 21137861304, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36854784000).

21137861304 is an abundant number, since it is smaller than the sum of its proper divisors (52571706696).

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

21137861304 is a wasteful number, since it uses less digits than its factorization.

21137861304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32055 (or 32045 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The spelling of 21137861304 in words is "twenty-one billion, one hundred thirty-seven million, eight hundred sixty-one thousand, three hundred four".