1296855857 has 20 divisors (see below), whose sum is σ = 1442299380. Its totient is φ = 1165956000.

The previous prime is 1296855839. The next prime is 1296855881. The reversal of 1296855857 is 7585586921.

It can be written as a sum of positive squares in 2 ways, for example, as 1180884496 + 115971361 = 34364^2 + 10769^2 .

It is not a de Polignac number, because 1296855857 - 2⁶ = 1296855793 is a prime.

It is a super-2 number, since 2×1296855857² = 3363670227670408898, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1296855817) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1478303 + ... + 1479179.

It is an arithmetic number, because the mean of its divisors is an integer number (72114969).

Almost surely, 2^1296855857 is an apocalyptic number.

It is an amenable number.

1296855857 is a deficient number, since it is larger than the sum of its proper divisors (145443523).

1296855857 is an frugal number, since it uses more digits than its factorization.

1296855857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1022 (or 989 counting only the distinct ones).

The product of its digits is 6048000, while the sum is 56.

The square root of 1296855857 is about 36011.8849409469. The cubic root of 1296855857 is about 1090.5123021751.

It can be divided in two parts, 12 and 96855857, that added together give a palindrome (96855869).

The spelling of 1296855857 in words is "one billion, two hundred ninety-six million, eight hundred fifty-five thousand, eight hundred fifty-seven".