21411815278464 has 768 divisors, whose sum is σ = 74696525205120. Its totient is φ = 5819118649344.

The previous prime is 21411815278463. The next prime is 21411815278471. The reversal of 21411815278464 is 46487251811412.

21411815278464 is a `hidden beast` number, since 2 + 1 + 41 + 18 + 1 + 527 + 8 + 4 + 64 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21411815278464.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21411815278463) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 310313152 + ... + 310382144.

Almost surely, 2^{21411815278464} is an apocalyptic number.

21411815278464 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 21411815278464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37348262602560).

21411815278464 is an abundant number, since it is smaller than the sum of its proper divisors (53284709926656).

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

21411815278464 is a wasteful number, since it uses less digits than its factorization.

21411815278464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69119 (or 69104 counting only the distinct ones).

The product of its digits is 3440640, while the sum is 54.

The spelling of 21411815278464 in words is "twenty-one trillion, four hundred eleven billion, eight hundred fifteen million, two hundred seventy-eight thousand, four hundred sixty-four".