1256742115 has 16 divisors (see below), whose sum is σ = 1583390880. Its totient is φ = 956229120.

The previous prime is 1256742101. The next prime is 1256742121. The reversal of 1256742115 is 5112476521.

It is not a de Polignac number, because 1256742115 - 2⁵ = 1256742083 is a prime.

It is a super-2 number, since 2×1256742115² = 3158801487229346450, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54966 + ... + 74395.

It is an arithmetic number, because the mean of its divisors is an integer number (98961930).

Almost surely, 2^1256742115 is an apocalyptic number.

1256742115 is a deficient number, since it is larger than the sum of its proper divisors (326648765).

1256742115 is a wasteful number, since it uses less digits than its factorization.

1256742115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129462.

The product of its digits is 16800, while the sum is 34.

The square root of 1256742115 is about 35450.5587403076. The cubic root of 1256742115 is about 1079.1505995696.

The spelling of 1256742115 in words is "one billion, two hundred fifty-six million, seven hundred forty-two thousand, one hundred fifteen".