21748926464 has 48 divisors (see below), whose sum is σ = 43540415100. Its totient is φ = 10861166592.

The previous prime is 21748926439. The next prime is 21748926533. The reversal of 21748926464 is 46462984712.

It can be written as a sum of positive squares in 2 ways, for example, as 15727166464 + 6021760000 = 125408^2 + 77600^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1790042 + ... + 1802150.

Almost surely, 2^21748926464 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 21748926464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21770207550).

21748926464 is an abundant number, since it is smaller than the sum of its proper divisors (21791488636).

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

21748926464 is an equidigital number, since it uses as much as digits as its factorization.

21748926464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13008 (or 12988 counting only the distinct ones).

The product of its digits is 4644864, while the sum is 53.

The spelling of 21748926464 in words is "twenty-one billion, seven hundred forty-eight million, nine hundred twenty-six thousand, four hundred sixty-four".