20455572247657 has 2 divisors, whose sum is σ = 20455572247658. Its totient is φ = 20455572247656.

The previous prime is 20455572247639. The next prime is 20455572247793. The reversal of 20455572247657 is 75674227555402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16178704220176 + 4276868027481 = 4022276^2 + 2068059^2 .

It is a cyclic number.

It is not a de Polignac number, because 20455572247657 - 2³⁵ = 20421212509289 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20455572247595 and 20455572247604.

It is not a weakly prime, because it can be changed into another prime (20455572247157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10227786123828 + 10227786123829.

It is an arithmetic number, because the mean of its divisors is an integer number (10227786123829).

Almost surely, 2^{20455572247657} is an apocalyptic number.

It is an amenable number.

20455572247657 is a deficient number, since it is larger than the sum of its proper divisors (1).

20455572247657 is an equidigital number, since it uses as much as digits as its factorization.

20455572247657 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 164640000, while the sum is 61.

The spelling of 20455572247657 in words is "twenty trillion, four hundred fifty-five billion, five hundred seventy-two million, two hundred forty-seven thousand, six hundred fifty-seven".