1256522265 has 24 divisors (see below), whose sum is σ = 2179052928. Its totient is φ = 669812640.

The previous prime is 1256522261. The next prime is 1256522291. The reversal of 1256522265 is 5622256521.

1256522265 is a `hidden beast` number, since 12 + 565 + 2 + 22 + 65 = 666.

It is not a de Polignac number, because 1256522265 - 2² = 1256522261 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1256522261) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 104410 + ... + 115820.

It is an arithmetic number, because the mean of its divisors is an integer number (90793872).

Almost surely, 2^1256522265 is an apocalyptic number.

1256522265 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1256522265 is a deficient number, since it is larger than the sum of its proper divisors (922530663).

1256522265 is a wasteful number, since it uses less digits than its factorization.

1256522265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13869 (or 13866 counting only the distinct ones).

The product of its digits is 72000, while the sum is 36.

The square root of 1256522265 is about 35447.4578072956. The cubic root of 1256522265 is about 1079.0876683094.

Adding to 1256522265 its reverse (5622256521), we get a palindrome (6878778786).

The spelling of 1256522265 in words is "one billion, two hundred fifty-six million, five hundred twenty-two thousand, two hundred sixty-five".