22665406638 has 64 divisors (see below), whose sum is σ = 54940515840. Its totient is φ = 6085297152.

The previous prime is 22665406613. The next prime is 22665406639. The reversal of 22665406638 is 83660456622.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22665406639) 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 31 ways as a sum of consecutive naturals, for example, 434418 + ... + 483786.

It is an arithmetic number, because the mean of its divisors is an integer number (858445560).

Almost surely, 2^22665406638 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22665406638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27470257920).

22665406638 is an abundant number, since it is smaller than the sum of its proper divisors (32275109202).

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

22665406638 is a wasteful number, since it uses less digits than its factorization.

22665406638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50041.

The product of its (nonzero) digits is 2488320, while the sum is 48.

The spelling of 22665406638 in words is "twenty-two billion, six hundred sixty-five million, four hundred six thousand, six hundred thirty-eight".