2631978257 has 2 divisors, whose sum is σ = 2631978258. Its totient is φ = 2631978256.

The previous prime is 2631978253. The next prime is 2631978269. The reversal of 2631978257 is 7528791362.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1739223616 + 892754641 = 41704^2 + 29879^2 .

It is a cyclic number.

It is not a de Polignac number, because 2631978257 - 2² = 2631978253 is a prime.

It is not a weakly prime, because it can be changed into another prime (2631978253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1315989128 + 1315989129.

It is an arithmetic number, because the mean of its divisors is an integer number (1315989129).

Almost surely, 2^2631978257 is an apocalyptic number.

It is an amenable number.

2631978257 is a deficient number, since it is larger than the sum of its proper divisors (1).

2631978257 is an equidigital number, since it uses as much as digits as its factorization.

2631978257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1270080, while the sum is 50.

The square root of 2631978257 is about 51302.8094454875. The cubic root of 2631978257 is about 1380.6833864088.

The spelling of 2631978257 in words is "two billion, six hundred thirty-one million, nine hundred seventy-eight thousand, two hundred fifty-seven".