1156161257 has 2 divisors, whose sum is σ = 1156161258. Its totient is φ = 1156161256.

The previous prime is 1156161233. The next prime is 1156161269. The reversal of 1156161257 is 7521616511.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 710275801 + 445885456 = 26651^2 + 21116^2 .

It is a cyclic number.

It is not a de Polignac number, because 1156161257 - 2¹⁸ = 1155899113 is a prime.

It is not a weakly prime, because it can be changed into another prime (1156169257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 578080628 + 578080629.

It is an arithmetic number, because the mean of its divisors is an integer number (578080629).

Almost surely, 2^1156161257 is an apocalyptic number.

It is an amenable number.

1156161257 is a deficient number, since it is larger than the sum of its proper divisors (1).

1156161257 is an equidigital number, since it uses as much as digits as its factorization.

1156161257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12600, while the sum is 35.

The square root of 1156161257 is about 34002.3713437754. The cubic root of 1156161257 is about 1049.5572606590.

Adding to 1156161257 its reverse (7521616511), we get a palindrome (8677777768).

The spelling of 1156161257 in words is "one billion, one hundred fifty-six million, one hundred sixty-one thousand, two hundred fifty-seven".