2661256457 has 2 divisors, whose sum is σ = 2661256458. Its totient is φ = 2661256456.

The previous prime is 2661256453. The next prime is 2661256553. The reversal of 2661256457 is 7546521662.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2201111056 + 460145401 = 46916^2 + 21451^2 .

It is a cyclic number.

It is not a de Polignac number, because 2661256457 - 2² = 2661256453 is a prime.

It is a super-3 number, since 3×2661256457³ (a number of 29 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (2661256453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1330628228 + 1330628229.

It is an arithmetic number, because the mean of its divisors is an integer number (1330628229).

Almost surely, 2^2661256457 is an apocalyptic number.

It is an amenable number.

2661256457 is a deficient number, since it is larger than the sum of its proper divisors (1).

2661256457 is an equidigital number, since it uses as much as digits as its factorization.

2661256457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 604800, while the sum is 44.

The square root of 2661256457 is about 51587.3672229937. The cubic root of 2661256457 is about 1385.7841063013.

The spelling of 2661256457 in words is "two billion, six hundred sixty-one million, two hundred fifty-six thousand, four hundred fifty-seven".