20318004397638 has 128 divisors (see below), whose sum is σ = 46675704176640. Its totient is φ = 6544627217280.

The previous prime is 20318004397637. The next prime is 20318004397763. The reversal of 20318004397638 is 83679340081302.

20318004397638 is a `hidden beast` number, since 2 + 0 + 31 + 80 + 0 + 439 + 76 + 38 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20318004397637) 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, 5760702631 + ... + 5760706157.

It is an arithmetic number, because the mean of its divisors is an integer number (364653938880).

Almost surely, 2^{20318004397638} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20318004397638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23337852088320).

20318004397638 is an abundant number, since it is smaller than the sum of its proper divisors (26357699779002).

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

20318004397638 is a wasteful number, since it uses less digits than its factorization.

20318004397638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7619 (or 7613 counting only the distinct ones).

The product of its (nonzero) digits is 5225472, while the sum is 54.

The spelling of 20318004397638 in words is "twenty trillion, three hundred eighteen billion, four million, three hundred ninety-seven thousand, six hundred thirty-eight".