21311873280 has 288 divisors, whose sum is σ = 77391726720. Its totient is φ = 5550612480.

The previous prime is 21311873239. The next prime is 21311873293. The reversal of 21311873280 is 8237811312.

21311873280 is a `hidden beast` number, since 213 + 118 + 7 + 328 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1478910 + ... + 1493250.

Almost surely, 2^21311873280 is an apocalyptic number.

21311873280 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 21311873280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38695863360).

21311873280 is an abundant number, since it is smaller than the sum of its proper divisors (56079853440).

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

21311873280 is a wasteful number, since it uses less digits than its factorization.

21311873280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14414 (or 14394 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The spelling of 21311873280 in words is "twenty-one billion, three hundred eleven million, eight hundred seventy-three thousand, two hundred eighty".