20357838638 has 4 divisors (see below), whose sum is σ = 30536757960. Its totient is φ = 10178919318.

The previous prime is 20357838617. The next prime is 20357838661. The reversal of 20357838638 is 83683875302.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83683875302 = 2 ⋅41841937651.

It is a self number, because there is not a number n which added to its sum of digits gives 20357838638.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5089459658 + ... + 5089459661.

It is an arithmetic number, because the mean of its divisors is an integer number (7634189490).

Almost surely, 2^20357838638 is an apocalyptic number.

20357838638 is a deficient number, since it is larger than the sum of its proper divisors (10178919322).

20357838638 is a wasteful number, since it uses less digits than its factorization.

20357838638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10178919321.

The product of its (nonzero) digits is 5806080, while the sum is 53.

The spelling of 20357838638 in words is "twenty billion, three hundred fifty-seven million, eight hundred thirty-eight thousand, six hundred thirty-eight".