1157216257 has 4 divisors (see below), whose sum is σ = 1179050580. Its totient is φ = 1135381936.

The previous prime is 1157216233. The next prime is 1157216279. The reversal of 1157216257 is 7526127511.

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 945193536 + 212022721 = 30744^2 + 14561^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1157216257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1157216297) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10917082 + ... + 10917187.

It is an arithmetic number, because the mean of its divisors is an integer number (294762645).

Almost surely, 2^1157216257 is an apocalyptic number.

It is an amenable number.

1157216257 is a deficient number, since it is larger than the sum of its proper divisors (21834323).

1157216257 is an equidigital number, since it uses as much as digits as its factorization.

1157216257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21834322.

The product of its digits is 29400, while the sum is 37.

The square root of 1157216257 is about 34017.8814302126. The cubic root of 1157216257 is about 1049.8764048022.

It can be divided in two parts, 115721625 and 7, that multiplied together give a triangular number (810051375 = T₄₀₂₅₀).

The spelling of 1157216257 in words is "one billion, one hundred fifty-seven million, two hundred sixteen thousand, two hundred fifty-seven".