66257255275265 has 4 divisors (see below), whose sum is σ = 79508706330324. Its totient is φ = 53005804220208.

The previous prime is 66257255275243. The next prime is 66257255275301. The reversal of 66257255275265 is 56257255275266.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 21530425927921 + 44726829347344 = 4640089^2 + 6687812^2 .

It is a cyclic number.

It is not a de Polignac number, because 66257255275265 - 2⁸ = 66257255275009 is a prime.

It is a super-2 number, since 2×66257255275265² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6625725527522 + ... + 6625725527531.

It is an arithmetic number, because the mean of its divisors is an integer number (19877176582581).

Almost surely, 2^{66257255275265} is an apocalyptic number.

It is an amenable number.

66257255275265 is a deficient number, since it is larger than the sum of its proper divisors (13251451055059).

66257255275265 is a wasteful number, since it uses less digits than its factorization.

66257255275265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13251451055058.

The product of its digits is 529200000, while the sum is 65.

Subtracting from 66257255275265 its reverse (56257255275266), we obtain a palindrome (9999999999999).

The spelling of 66257255275265 in words is "sixty-six trillion, two hundred fifty-seven billion, two hundred fifty-five million, two hundred seventy-five thousand, two hundred sixty-five".