1161551641 has 2 divisors, whose sum is σ = 1161551642. Its totient is φ = 1161551640.

The previous prime is 1161551627. The next prime is 1161551669. The reversal of 1161551641 is 1461551611.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 973752025 + 187799616 = 31205^2 + 13704^2 .

It is a cyclic number.

It is not a de Polignac number, because 1161551641 - 2⁵ = 1161551609 is a prime.

It is not a weakly prime, because it can be changed into another prime (1161551341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 580775820 + 580775821.

It is an arithmetic number, because the mean of its divisors is an integer number (580775821).

Almost surely, 2^1161551641 is an apocalyptic number.

It is an amenable number.

1161551641 is a deficient number, since it is larger than the sum of its proper divisors (1).

1161551641 is an equidigital number, since it uses as much as digits as its factorization.

1161551641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3600, while the sum is 31.

The square root of 1161551641 is about 34081.5439937806. The cubic root of 1161551641 is about 1051.1858532582.

The spelling of 1161551641 in words is "one billion, one hundred sixty-one million, five hundred fifty-one thousand, six hundred forty-one".