1649599957 has 2 divisors, whose sum is σ = 1649599958. Its totient is φ = 1649599956.

The previous prime is 1649599949. The next prime is 1649599979. The reversal of 1649599957 is 7599959461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1347917796 + 301682161 = 36714^2 + 17369^2 .

It is a cyclic number.

It is not a de Polignac number, because 1649599957 - 2³ = 1649599949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1649599657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 824799978 + 824799979.

It is an arithmetic number, because the mean of its divisors is an integer number (824799979).

Almost surely, 2^1649599957 is an apocalyptic number.

It is an amenable number.

1649599957 is a deficient number, since it is larger than the sum of its proper divisors (1).

1649599957 is an equidigital number, since it uses as much as digits as its factorization.

1649599957 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27556200, while the sum is 64.

The square root of 1649599957 is about 40615.2675357433. The cubic root of 1649599957 is about 1181.5702443422.

The spelling of 1649599957 in words is "one billion, six hundred forty-nine million, five hundred ninety-nine thousand, nine hundred fifty-seven".