3646657991 has 2 divisors, whose sum is σ = 3646657992. Its totient is φ = 3646657990.

The previous prime is 3646657967. The next prime is 3646658023. The reversal of 3646657991 is 1997566463.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3646657991 - 2¹⁰ = 3646656967 is a prime.

It is a super-2 number, since 2×3646657991² = 26596229006648312162, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3646657901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1823328995 + 1823328996.

It is an arithmetic number, because the mean of its divisors is an integer number (1823328996).

Almost surely, 2^3646657991 is an apocalyptic number.

3646657991 is a deficient number, since it is larger than the sum of its proper divisors (1).

3646657991 is an equidigital number, since it uses as much as digits as its factorization.

3646657991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7348320, while the sum is 56.

The square root of 3646657991 is about 60387.5648705924. The cubic root of 3646657991 is about 1539.2116602370.

The spelling of 3646657991 in words is "three billion, six hundred forty-six million, six hundred fifty-seven thousand, nine hundred ninety-one".