649766731 has 16 divisors (see below), whose sum is σ = 706237600. Its totient is φ = 595703808.

The previous prime is 649766687. The next prime is 649766743. The reversal of 649766731 is 137667946.

It is a happy number.

It is not a de Polignac number, because 649766731 - 2⁹ = 649766219 is a prime.

It is a super-2 number, since 2×649766731² = 844393609428852722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (649766791) 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 15 ways as a sum of consecutive naturals, for example, 133285 + ... + 138073.

It is an arithmetic number, because the mean of its divisors is an integer number (44139850).

Almost surely, 2^649766731 is an apocalyptic number.

649766731 is a deficient number, since it is larger than the sum of its proper divisors (56470869).

649766731 is a wasteful number, since it uses less digits than its factorization.

649766731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5038.

The product of its digits is 1143072, while the sum is 49.

The square root of 649766731 is about 25490.5223759734. The cubic root of 649766731 is about 866.1354689784.

The spelling of 649766731 in words is "six hundred forty-nine million, seven hundred sixty-six thousand, seven hundred thirty-one".