649952640 has 256 divisors, whose sum is σ = 2383128000. Its totient is φ = 167215104.

The previous prime is 649952629. The next prime is 649952647. The reversal of 649952640 is 46259946.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649952647) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 500472 + ... + 501768.

Almost surely, 2^649952640 is an apocalyptic number.

649952640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 649952640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1191564000).

649952640 is an abundant number, since it is smaller than the sum of its proper divisors (1733175360).

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

649952640 is a wasteful number, since it uses less digits than its factorization.

649952640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1354 (or 1336 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 45.

The square root of 649952640 is about 25494.1687450287. The cubic root of 649952640 is about 866.2180663253.

The spelling of 649952640 in words is "six hundred forty-nine million, nine hundred fifty-two thousand, six hundred forty".