1649612257 has 2 divisors, whose sum is σ = 1649612258. Its totient is φ = 1649612256.

The previous prime is 1649612231. The next prime is 1649612309. The reversal of 1649612257 is 7522169461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1580539536 + 69072721 = 39756^2 + 8311^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1649612257 is a prime.

It is not a weakly prime, because it can be changed into another prime (1649612557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 824806128 + 824806129.

It is an arithmetic number, because the mean of its divisors is an integer number (824806129).

Almost surely, 2^1649612257 is an apocalyptic number.

It is an amenable number.

1649612257 is a deficient number, since it is larger than the sum of its proper divisors (1).

1649612257 is an equidigital number, since it uses as much as digits as its factorization.

1649612257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 181440, while the sum is 43.

The square root of 1649612257 is about 40615.4189563520. The cubic root of 1649612257 is about 1181.5731810699.

The spelling of 1649612257 in words is "one billion, six hundred forty-nine million, six hundred twelve thousand, two hundred fifty-seven".