18939644262 has 128 divisors (see below), whose sum is σ = 54755205120. Its totient is φ = 4705477920.

The previous prime is 18939644261. The next prime is 18939644279. The reversal of 18939644262 is 26244693981.

18939644262 is a `hidden beast` number, since 189 + 39 + 6 + 4 + 426 + 2 = 666.

It is a super-2 number, since 2×18939644262² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 18939644199 and 18939644208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18939644261) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3388 + ... + 194655.

It is an arithmetic number, because the mean of its divisors is an integer number (427775040).

Almost surely, 2^18939644262 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18939644262, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27377602560).

18939644262 is an abundant number, since it is smaller than the sum of its proper divisors (35815560858).

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

18939644262 is a wasteful number, since it uses less digits than its factorization.

18939644262 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198095 (or 198089 counting only the distinct ones).

The product of its digits is 4478976, while the sum is 54.

The spelling of 18939644262 in words is "eighteen billion, nine hundred thirty-nine million, six hundred forty-four thousand, two hundred sixty-two".