2657685718081 has 9 divisors (see below), whose sum is σ = 2684426280969. Its totient is φ = 2631208974000.

The previous prime is 2657685718073. The next prime is 2657685718159. The reversal of 2657685718081 is 1808175867562.

The square root of 2657685718081 is 1630241.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 596278940481 + 2061406777600 = 772191^2 + 1435760^2 .

It is not a de Polignac number, because 2657685718081 - 2³ = 2657685718073 is a prime.

It is a super-2 number, since 2×2657685718081² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2657685718981) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 164646271 + ... + 164662411.

Almost surely, 2^{2657685718081} is an apocalyptic number.

2657685718081 is the 1630241-st square number.

2657685718081 is the 815121-st centered octagonal number.

It is an amenable number.

2657685718081 is a deficient number, since it is larger than the sum of its proper divisors (26740562888).

2657685718081 is an frugal number, since it uses more digits than its factorization.

2657685718081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32484 (or 16242 counting only the distinct ones).

The product of its (nonzero) digits is 45158400, while the sum is 64.

Multiplying 2657685718081 by its sum of digits (64), we get a square (170091885957184 = 13041928²).

The spelling of 2657685718081 in words is "two trillion, six hundred fifty-seven billion, six hundred eighty-five million, seven hundred eighteen thousand, eighty-one".