21326312448 has 440 divisors, whose sum is σ = 75994334592. Its totient is φ = 5824659456.

The previous prime is 21326312437. The next prime is 21326312459. The reversal of 21326312448 is 84421362312.

21326312448 is a `hidden beast` number, since 2 + 13 + 2 + 631 + 2 + 4 + 4 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (21326312437) and next prime (21326312459).

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

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 13353186 + ... + 13354782.

Almost surely, 2^21326312448 is an apocalyptic number.

21326312448 is a gapful number since it is divisible by the number (28) 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 21326312448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37997167296).

21326312448 is an abundant number, since it is smaller than the sum of its proper divisors (54668022144).

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

21326312448 is a wasteful number, since it uses less digits than its factorization.

21326312448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1659 (or 1632 counting only the distinct ones).

The product of its digits is 55296, while the sum is 36.

The spelling of 21326312448 in words is "twenty-one billion, three hundred twenty-six million, three hundred twelve thousand, four hundred forty-eight".