21320410638 has 8 divisors (see below), whose sum is σ = 42640821288. Its totient is φ = 7106803544.

The previous prime is 21320410637. The next prime is 21320410757. The reversal of 21320410638 is 83601402312.

It is a sphenic number, since it is the product of 3 distinct primes.

21320410638 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21320410633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1776700881 + ... + 1776700892.

It is an arithmetic number, because the mean of its divisors is an integer number (5330102661).

Almost surely, 2^21320410638 is an apocalyptic number.

21320410638 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21320410638 is a wasteful number, since it uses less digits than its factorization.

21320410638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3553401778.

The product of its (nonzero) digits is 6912, while the sum is 30.

The spelling of 21320410638 in words is "twenty-one billion, three hundred twenty million, four hundred ten thousand, six hundred thirty-eight".