649981266 has 24 divisors (see below), whose sum is σ = 1428886032. Its totient is φ = 196963800.

The previous prime is 649981253. The next prime is 649981289. The reversal of 649981266 is 662189946.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 446920 + ... + 448371.

It is an arithmetic number, because the mean of its divisors is an integer number (59536918).

Almost surely, 2^649981266 is an apocalyptic number.

649981266 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

649981266 is an abundant number, since it is smaller than the sum of its proper divisors (778904766).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

649981266 is a wasteful number, since it uses less digits than its factorization.

649981266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 895318 (or 895307 counting only the distinct ones).

The product of its digits is 1119744, while the sum is 51.

The square root of 649981266 is about 25494.7301613490. The cubic root of 649981266 is about 866.2307831464.

The spelling of 649981266 in words is "six hundred forty-nine million, nine hundred eighty-one thousand, two hundred sixty-six".