20620665638 has 8 divisors (see below), whose sum is σ = 30931708440. Its totient is φ = 10310096160.

The previous prime is 20620665551. The next prime is 20620665641. The reversal of 20620665638 is 83656602602.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25598 + ... + 204686.

It is an arithmetic number, because the mean of its divisors is an integer number (3866463555).

Almost surely, 2^20620665638 is an apocalyptic number.

20620665638 is a deficient number, since it is larger than the sum of its proper divisors (10311042802).

20620665638 is a wasteful number, since it uses less digits than its factorization.

20620665638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236662.

The product of its (nonzero) digits is 622080, while the sum is 44.

The spelling of 20620665638 in words is "twenty billion, six hundred twenty million, six hundred sixty-five thousand, six hundred thirty-eight".