649340666 has 16 divisors (see below), whose sum is σ = 1066716000. Its totient is φ = 294615408.

The previous prime is 649340651. The next prime is 649340677. The reversal of 649340666 is 666043946.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 210116 + ... + 213183.

It is an arithmetic number, because the mean of its divisors is an integer number (66669750).

Almost surely, 2^649340666 is an apocalyptic number.

649340666 is a deficient number, since it is larger than the sum of its proper divisors (417375334).

649340666 is a wasteful number, since it uses less digits than its factorization.

649340666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 423373.

The product of its (nonzero) digits is 559872, while the sum is 44.

The square root of 649340666 is about 25482.1636836435. The cubic root of 649340666 is about 865.9461134859.

The spelling of 649340666 in words is "six hundred forty-nine million, three hundred forty thousand, six hundred sixty-six".