1556451161 has 2 divisors, whose sum is σ = 1556451162. Its totient is φ = 1556451160.

The previous prime is 1556451157. The next prime is 1556451179. The reversal of 1556451161 is 1611546551.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 983136025 + 573315136 = 31355^2 + 23944^2 .

It is a cyclic number.

It is not a de Polignac number, because 1556451161 - 2² = 1556451157 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1556451191) 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, 778225580 + 778225581.

It is an arithmetic number, because the mean of its divisors is an integer number (778225581).

Almost surely, 2^1556451161 is an apocalyptic number.

It is an amenable number.

1556451161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1556451161 is an equidigital number, since it uses as much as digits as its factorization.

1556451161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18000, while the sum is 35.

The square root of 1556451161 is about 39451.8841248425. The cubic root of 1556451161 is about 1158.8978733753.

The spelling of 1556451161 in words is "one billion, five hundred fifty-six million, four hundred fifty-one thousand, one hundred sixty-one".