649128992 has 12 divisors (see below), whose sum is σ = 1277972766. Its totient is φ = 324564480.

The previous prime is 649128983. The next prime is 649129021. The reversal of 649128992 is 299821946.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 647397136 + 1731856 = 25444^2 + 1316^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 649128992.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10142609 + ... + 10142672.

Almost surely, 2^649128992 is an apocalyptic number.

It is an amenable number.

649128992 is a deficient number, since it is larger than the sum of its proper divisors (628843774).

649128992 is a wasteful number, since it uses less digits than its factorization.

649128992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20285291 (or 20285283 counting only the distinct ones).

The product of its digits is 559872, while the sum is 50.

The square root of 649128992 is about 25478.0099693834. The cubic root of 649128992 is about 865.8520086971.

The spelling of 649128992 in words is "six hundred forty-nine million, one hundred twenty-eight thousand, nine hundred ninety-two".