1161599555 has 4 divisors (see below), whose sum is σ = 1393919472. Its totient is φ = 929279640.

The previous prime is 1161599539. The next prime is 1161599563. The reversal of 1161599555 is 5559951611.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5559951611 = 2131 ⋅2609081.

It is not a de Polignac number, because 1161599555 - 2⁴ = 1161599539 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 116159951 + ... + 116159960.

It is an arithmetic number, because the mean of its divisors is an integer number (348479868).

Almost surely, 2^1161599555 is an apocalyptic number.

1161599555 is a deficient number, since it is larger than the sum of its proper divisors (232319917).

1161599555 is an equidigital number, since it uses as much as digits as its factorization.

1161599555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232319916.

The product of its digits is 303750, while the sum is 47.

The square root of 1161599555 is about 34082.2469183004. The cubic root of 1161599555 is about 1051.2003068633.

The spelling of 1161599555 in words is "one billion, one hundred sixty-one million, five hundred ninety-nine thousand, five hundred fifty-five".