2991681569 has 2 divisors, whose sum is σ = 2991681570. Its totient is φ = 2991681568.

The previous prime is 2991681551. The next prime is 2991681643. The reversal of 2991681569 is 9651861992.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2968833169 + 22848400 = 54487^2 + 4780^2 .

It is a cyclic number.

It is not a de Polignac number, because 2991681569 - 2⁸ = 2991681313 is a prime.

It is a super-2 number, since 2×2991681569² = 17900317220588603522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2991686569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1495840784 + 1495840785.

It is an arithmetic number, because the mean of its divisors is an integer number (1495840785).

Almost surely, 2^2991681569 is an apocalyptic number.

It is an amenable number.

2991681569 is a deficient number, since it is larger than the sum of its proper divisors (1).

2991681569 is an equidigital number, since it uses as much as digits as its factorization.

2991681569 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2099520, while the sum is 56.

The square root of 2991681569 is about 54696.2664996433. The cubic root of 2991681569 is about 1440.9153081572.

The spelling of 2991681569 in words is "two billion, nine hundred ninety-one million, six hundred eighty-one thousand, five hundred sixty-nine".