20573977973 has 4 divisors (see below), whose sum is σ = 20654032620. Its totient is φ = 20493923328.

The previous prime is 20573977951. The next prime is 20573978059. The reversal of 20573977973 is 37977937502.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11173124209 + 9400853764 = 105703^2 + 96958^2 .

It is a cyclic number.

It is not a de Polignac number, because 20573977973 - 2²⁰ = 20572929397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20573977943) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40026938 + ... + 40027451.

It is an arithmetic number, because the mean of its divisors is an integer number (5163508155).

Almost surely, 2^20573977973 is an apocalyptic number.

It is an amenable number.

20573977973 is a deficient number, since it is larger than the sum of its proper divisors (80054647).

20573977973 is an equidigital number, since it uses as much as digits as its factorization.

20573977973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80054646.

The product of its (nonzero) digits is 17503290, while the sum is 59.

The spelling of 20573977973 in words is "twenty billion, five hundred seventy-three million, nine hundred seventy-seven thousand, nine hundred seventy-three".