21426844590 has 96 divisors (see below), whose sum is σ = 57785551200. Its totient is φ = 5501986560.

The previous prime is 21426844577. The next prime is 21426844601. The reversal of 21426844590 is 9544862412.

It is a happy number.

21426844590 is a `hidden beast` number, since 2 + 14 + 2 + 6 + 8 + 44 + 590 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

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, 978360 + ... + 1000020.

It is an arithmetic number, because the mean of its divisors is an integer number (601932825).

Almost surely, 2^21426844590 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21426844590, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28892775600).

21426844590 is an abundant number, since it is smaller than the sum of its proper divisors (36358706610).

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

21426844590 is a wasteful number, since it uses less digits than its factorization.

21426844590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22082 (or 22079 counting only the distinct ones).

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

The spelling of 21426844590 in words is "twenty-one billion, four hundred twenty-six million, eight hundred forty-four thousand, five hundred ninety".