649399660 has 192 divisors, whose sum is σ = 1801820160. Its totient is φ = 190771200.

The previous prime is 649399603. The next prime is 649399721. The reversal of 649399660 is 66993946.

It is a happy number.

649399660 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (52).

It is a junction number, because it is equal to n+sod(n) for n = 649399598 and 649399607.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4300585 + ... + 4300735.

It is an arithmetic number, because the mean of its divisors is an integer number (9384480).

Almost surely, 2^649399660 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 649399660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (900910080).

649399660 is an abundant number, since it is smaller than the sum of its proper divisors (1152420500).

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

649399660 is a wasteful number, since it uses less digits than its factorization.

649399660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336 (or 334 counting only the distinct ones).

The product of its (nonzero) digits is 1889568, while the sum is 52.

The square root of 649399660 is about 25483.3212121183. The cubic root of 649399660 is about 865.9723370491.

The spelling of 649399660 in words is "six hundred forty-nine million, three hundred ninety-nine thousand, six hundred sixty".