20784268057 has 8 divisors (see below), whose sum is σ = 23776058432. Its totient is φ = 17798130000.

The previous prime is 20784268039. The next prime is 20784268081. The reversal of 20784268057 is 75086248702.

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

It is not a de Polignac number, because 20784268057 - 2³¹ = 18636784409 is a prime.

It is the 144168-th Hogben number.

It is a self number, because there is not a number n which added to its sum of digits gives 20784268057.

It is not an unprimeable number, because it can be changed into a prime (20784268007) by changing a digit.

It is a nontrivial repunit in base 144167.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1405194 + ... + 1419907.

It is an arithmetic number, because the mean of its divisors is an integer number (2972007304).

Almost surely, 2^20784268057 is an apocalyptic number.

It is an amenable number.

20784268057 is a deficient number, since it is larger than the sum of its proper divisors (2991790375).

20784268057 is a wasteful number, since it uses less digits than its factorization.

20784268057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2826159.

The product of its (nonzero) digits is 1505280, while the sum is 49.

The spelling of 20784268057 in words is "twenty billion, seven hundred eighty-four million, two hundred sixty-eight thousand, fifty-seven".