21426254928 has 240 divisors, whose sum is σ = 65485114240. Its totient is φ = 6500736000.

The previous prime is 21426254921. The next prime is 21426254953. The reversal of 21426254928 is 82945262412.

21426254928 is a `hidden beast` number, since 2 + 1 + 42 + 62 + 549 + 2 + 8 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21426254921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 64731723 + ... + 64732053.

Almost surely, 2^21426254928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21426254928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32742557120).

21426254928 is an abundant number, since it is smaller than the sum of its proper divisors (44058859312).

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

21426254928 is a wasteful number, since it uses less digits than its factorization.

21426254928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 738 (or 729 counting only the distinct ones).

The product of its digits is 552960, while the sum is 45.

The spelling of 21426254928 in words is "twenty-one billion, four hundred twenty-six million, two hundred fifty-four thousand, nine hundred twenty-eight".