20677017445561 has 4 divisors (see below), whose sum is σ = 21157878316432. Its totient is φ = 20196156574692.

The previous prime is 20677017445541. The next prime is 20677017445589. The reversal of 20677017445561 is 16554471077602.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20677017445561 - 2¹¹ = 20677017443513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20677017445531) 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, 240430435371 + ... + 240430435456.

It is an arithmetic number, because the mean of its divisors is an integer number (5289469579108).

Almost surely, 2^{20677017445561} is an apocalyptic number.

It is an amenable number.

20677017445561 is a deficient number, since it is larger than the sum of its proper divisors (480860870871).

20677017445561 is an equidigital number, since it uses as much as digits as its factorization.

20677017445561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 480860870870.

The product of its (nonzero) digits is 9878400, while the sum is 55.

The spelling of 20677017445561 in words is "twenty trillion, six hundred seventy-seven billion, seventeen million, four hundred forty-five thousand, five hundred sixty-one".