1256122065 has 64 divisors (see below), whose sum is σ = 2289353472. Its totient is φ = 582681600.

The previous prime is 1256122057. The next prime is 1256122067. The reversal of 1256122065 is 5602216521.

It is not a de Polignac number, because 1256122065 - 2³ = 1256122057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1256122067) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 370719 + ... + 374091.

It is an arithmetic number, because the mean of its divisors is an integer number (35771148).

Almost surely, 2^1256122065 is an apocalyptic number.

1256122065 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1256122065 is a deficient number, since it is larger than the sum of its proper divisors (1033231407).

1256122065 is a wasteful number, since it uses less digits than its factorization.

1256122065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3490.

The product of its (nonzero) digits is 7200, while the sum is 30.

The square root of 1256122065 is about 35441.8123831161. The cubic root of 1256122065 is about 1078.9730936741.

Adding to 1256122065 its reverse (5602216521), we get a palindrome (6858338586).

It can be divided in two parts, 1256 and 122065, that added together give a palindrome (123321).

The spelling of 1256122065 in words is "one billion, two hundred fifty-six million, one hundred twenty-two thousand, sixty-five".