21255426324 has 96 divisors (see below), whose sum is σ = 60162170880. Its totient is φ = 6436130400.

The previous prime is 21255426319. The next prime is 21255426337. The reversal of 21255426324 is 42362455212.

21255426324 is a `hidden beast` number, since 2 + 12 + 5 + 5 + 4 + 2 + 632 + 4 = 666.

It is a super-3 number, since 3×21255426324³ (a number of 32 digits) contains 333 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1741467 + ... + 1753629.

It is an arithmetic number, because the mean of its divisors is an integer number (626689280).

Almost surely, 2^21255426324 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 21255426324, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30081085440).

21255426324 is an abundant number, since it is smaller than the sum of its proper divisors (38906744556).

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

21255426324 is a wasteful number, since it uses less digits than its factorization.

21255426324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13658 (or 13650 counting only the distinct ones).

The product of its digits is 115200, while the sum is 36.

The spelling of 21255426324 in words is "twenty-one billion, two hundred fifty-five million, four hundred twenty-six thousand, three hundred twenty-four".