2056978661 has 2 divisors, whose sum is σ = 2056978662. Its totient is φ = 2056978660.

The previous prime is 2056978657. The next prime is 2056978667. The reversal of 2056978661 is 1668796502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1936528036 + 120450625 = 44006^2 + 10975^2 .

It is a cyclic number.

It is not a de Polignac number, because 2056978661 - 2² = 2056978657 is a prime.

It is a super-2 number, since 2×2056978661² = 8462322423618705842, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2056978667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1028489330 + 1028489331.

It is an arithmetic number, because the mean of its divisors is an integer number (1028489331).

Almost surely, 2^2056978661 is an apocalyptic number.

It is an amenable number.

2056978661 is a deficient number, since it is larger than the sum of its proper divisors (1).

2056978661 is an equidigital number, since it uses as much as digits as its factorization.

2056978661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1088640, while the sum is 50.

The square root of 2056978661 is about 45353.9266326522. The cubic root of 2056978661 is about 1271.7739611019.

The spelling of 2056978661 in words is "two billion, fifty-six million, nine hundred seventy-eight thousand, six hundred sixty-one".