2561505161701 has 2 divisors, whose sum is σ = 2561505161702. Its totient is φ = 2561505161700.

The previous prime is 2561505161671. The next prime is 2561505161711. The reversal of 2561505161701 is 1071615051652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2497458712225 + 64046449476 = 1580335^2 + 253074^2 .

It is a cyclic number.

It is not a de Polignac number, because 2561505161701 - 2²³ = 2561496773093 is a prime.

It is a super-2 number, since 2×2561505161701² (a number of 26 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2561505161711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1280752580850 + 1280752580851.

It is an arithmetic number, because the mean of its divisors is an integer number (1280752580851).

Almost surely, 2^{2561505161701} is an apocalyptic number.

It is an amenable number.

2561505161701 is a deficient number, since it is larger than the sum of its proper divisors (1).

2561505161701 is an equidigital number, since it uses as much as digits as its factorization.

2561505161701 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 63000, while the sum is 40.

The spelling of 2561505161701 in words is "two trillion, five hundred sixty-one billion, five hundred five million, one hundred sixty-one thousand, seven hundred one".