1649659731 has 4 divisors (see below), whose sum is σ = 2199546312. Its totient is φ = 1099773152.

The previous prime is 1649659717. The next prime is 1649659741. The reversal of 1649659731 is 1379569461.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1649659731 - 2⁷ = 1649659603 is a prime.

It is a super-2 number, since 2×1649659731² = 5442754456165984722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1649659741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 274943286 + ... + 274943291.

It is an arithmetic number, because the mean of its divisors is an integer number (549886578).

Almost surely, 2^1649659731 is an apocalyptic number.

1649659731 is a deficient number, since it is larger than the sum of its proper divisors (549886581).

1649659731 is an equidigital number, since it uses as much as digits as its factorization.

1649659731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 549886580.

The product of its digits is 1224720, while the sum is 51.

The square root of 1649659731 is about 40616.0033853652. The cubic root of 1649659731 is about 1181.5845157471.

The spelling of 1649659731 in words is "one billion, six hundred forty-nine million, six hundred fifty-nine thousand, seven hundred thirty-one".