20591398538 has 8 divisors (see below), whose sum is σ = 30888381888. Its totient is φ = 10295271244.

The previous prime is 20591398507. The next prime is 20591398543. The reversal of 20591398538 is 83589319502.

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20591398538.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 150056 + ... + 252387.

It is an arithmetic number, because the mean of its divisors is an integer number (3861047736).

Almost surely, 2^20591398538 is an apocalyptic number.

20591398538 is a deficient number, since it is larger than the sum of its proper divisors (10296983350).

20591398538 is a wasteful number, since it uses less digits than its factorization.

20591398538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428028.

The product of its (nonzero) digits is 2332800, while the sum is 53.

The spelling of 20591398538 in words is "twenty billion, five hundred ninety-one million, three hundred ninety-eight thousand, five hundred thirty-eight".