2057215661 has 2 divisors, whose sum is σ = 2057215662. Its totient is φ = 2057215660.

The previous prime is 2057215649. The next prime is 2057215669. The reversal of 2057215661 is 1665127502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1447422025 + 609793636 = 38045^2 + 24694^2 .

It is a cyclic number.

It is not a de Polignac number, because 2057215661 - 2⁶ = 2057215597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2057215669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1028607830 + 1028607831.

It is an arithmetic number, because the mean of its divisors is an integer number (1028607831).

Almost surely, 2^2057215661 is an apocalyptic number.

It is an amenable number.

2057215661 is a deficient number, since it is larger than the sum of its proper divisors (1).

2057215661 is an equidigital number, since it uses as much as digits as its factorization.

2057215661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25200, while the sum is 35.

The square root of 2057215661 is about 45356.5393410917. The cubic root of 2057215661 is about 1271.8228027775.

The spelling of 2057215661 in words is "two billion, fifty-seven million, two hundred fifteen thousand, six hundred sixty-one".