2312081561 has 2 divisors, whose sum is σ = 2312081562. Its totient is φ = 2312081560.

The previous prime is 2312081543. The next prime is 2312081657. The reversal of 2312081561 is 1651802132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1676083600 + 635997961 = 40940^2 + 25219^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2312081561 is a prime.

It is a super-2 number, since 2×2312081561² = 10691442289432393442, which contains 22 as substring.

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 (2312081461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1156040780 + 1156040781.

It is an arithmetic number, because the mean of its divisors is an integer number (1156040781).

Almost surely, 2^2312081561 is an apocalyptic number.

It is an amenable number.

2312081561 is a deficient number, since it is larger than the sum of its proper divisors (1).

2312081561 is an equidigital number, since it uses as much as digits as its factorization.

2312081561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 2312081561 is about 48084.1092357964. The cubic root of 2312081561 is about 1322.3133525184.

Adding to 2312081561 its reverse (1651802132), we get a palindrome (3963883693).

The spelling of 2312081561 in words is "two billion, three hundred twelve million, eighty-one thousand, five hundred sixty-one".