649198665 has 32 divisors (see below), whose sum is σ = 1162972800. Its totient is φ = 343586880.

The previous prime is 649198637. The next prime is 649198687. The reversal of 649198665 is 566891946.

It is a happy number.

649198665 is a `hidden beast` number, since 6 + 491 + 98 + 6 + 65 = 666.

It is not a de Polignac number, because 649198665 - 2⁸ = 649198409 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 670 + ... + 36039.

It is an arithmetic number, because the mean of its divisors is an integer number (36342900).

Almost surely, 2^649198665 is an apocalyptic number.

It is an amenable number.

649198665 is a deficient number, since it is larger than the sum of its proper divisors (513774135).

649198665 is a wasteful number, since it uses less digits than its factorization.

649198665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36854 (or 36848 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 54.

The square root of 649198665 is about 25479.3772490616. The cubic root of 649198665 is about 865.8829857702.

The spelling of 649198665 in words is "six hundred forty-nine million, one hundred ninety-eight thousand, six hundred sixty-five".