21481966838340 has 240 divisors, whose sum is σ = 68851939064832. Its totient is φ = 5604328306944.

The previous prime is 21481966838047. The next prime is 21481966838377. The reversal of 21481966838340 is 4383866918412.

21481966838340 is a `hidden beast` number, since 2 + 1 + 4 + 8 + 196 + 68 + 383 + 4 + 0 = 666.

It is a super-2 number, since 2×21481966838340² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 188541829 + ... + 188655731.

Almost surely, 2^{21481966838340} is an apocalyptic number.

21481966838340 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 21481966838340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34425969532416).

21481966838340 is an abundant number, since it is smaller than the sum of its proper divisors (47369972226492).

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

21481966838340 is a wasteful number, since it uses less digits than its factorization.

21481966838340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116448 (or 116437 counting only the distinct ones).

The product of its (nonzero) digits is 47775744, while the sum is 63.

The spelling of 21481966838340 in words is "twenty-one trillion, four hundred eighty-one billion, nine hundred sixty-six million, eight hundred thirty-eight thousand, three hundred forty".