20525401650557 has 2 divisors, whose sum is σ = 20525401650558. Its totient is φ = 20525401650556.

The previous prime is 20525401650541. The next prime is 20525401650563. The reversal of 20525401650557 is 75505610452502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11912755608196 + 8612646042361 = 3451486^2 + 2934731^2 .

It is a cyclic number.

It is not a de Polignac number, because 20525401650557 - 2⁴ = 20525401650541 is a prime.

It is a super-2 number, since 2×20525401650557² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20525401650527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10262700825278 + 10262700825279.

It is an arithmetic number, because the mean of its divisors is an integer number (10262700825279).

Almost surely, 2^{20525401650557} is an apocalyptic number.

It is an amenable number.

20525401650557 is a deficient number, since it is larger than the sum of its proper divisors (1).

20525401650557 is an equidigital number, since it uses as much as digits as its factorization.

20525401650557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2100000, while the sum is 47.

The spelling of 20525401650557 in words is "twenty trillion, five hundred twenty-five billion, four hundred one million, six hundred fifty thousand, five hundred fifty-seven".