1655787161557 has 2 divisors, whose sum is σ = 1655787161558. Its totient is φ = 1655787161556.

The previous prime is 1655787161467. The next prime is 1655787161627. The reversal of 1655787161557 is 7551617875561.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1379154291876 + 276632869681 = 1174374^2 + 525959^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1655787161557 is a prime.

It is a super-2 number, since 2×1655787161557² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1655787161257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 827893580778 + 827893580779.

It is an arithmetic number, because the mean of its divisors is an integer number (827893580779).

Almost surely, 2^{1655787161557} is an apocalyptic number.

It is an amenable number.

1655787161557 is a deficient number, since it is larger than the sum of its proper divisors (1).

1655787161557 is an equidigital number, since it uses as much as digits as its factorization.

1655787161557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 61740000, while the sum is 64.

The spelling of 1655787161557 in words is "one trillion, six hundred fifty-five billion, seven hundred eighty-seven million, one hundred sixty-one thousand, five hundred fifty-seven".