21427538496 has 336 divisors, whose sum is σ = 74769024960. Its totient is φ = 5353205760.

The previous prime is 21427538459. The next prime is 21427538533. The reversal of 21427538496 is 69483572412.

It is an interprime number because it is at equal distance from previous prime (21427538459) and next prime (21427538533).

It is a tau number, because it is divible by the number of its divisors (336).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2319166 + ... + 2328386.

It is an arithmetic number, because the mean of its divisors is an integer number (222526860).

Almost surely, 2^21427538496 is an apocalyptic number.

21427538496 is a gapful number since it is divisible by the number (26) 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 21427538496, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37384512480).

21427538496 is an abundant number, since it is smaller than the sum of its proper divisors (53341486464).

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

21427538496 is a wasteful number, since it uses less digits than its factorization.

21427538496 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9282 (or 9265 counting only the distinct ones).

The product of its digits is 2903040, while the sum is 51.

The spelling of 21427538496 in words is "twenty-one billion, four hundred twenty-seven million, five hundred thirty-eight thousand, four hundred ninety-six".