20572121567 has 4 divisors (see below), whose sum is σ = 20642333880. Its totient is φ = 20501909256.

The previous prime is 20572121551. The next prime is 20572121573. The reversal of 20572121567 is 76512127502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20572121567 - 2⁴ = 20572121551 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20572121567.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20572121267) by changing a digit.

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, 35105717 + ... + 35106302.

It is an arithmetic number, because the mean of its divisors is an integer number (5160583470).

Almost surely, 2^20572121567 is an apocalyptic number.

20572121567 is a deficient number, since it is larger than the sum of its proper divisors (70212313).

20572121567 is an equidigital number, since it uses as much as digits as its factorization.

20572121567 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70212312.

The product of its (nonzero) digits is 58800, while the sum is 38.

The spelling of 20572121567 in words is "twenty billion, five hundred seventy-two million, one hundred twenty-one thousand, five hundred sixty-seven".