649625440 has 24 divisors (see below), whose sum is σ = 1534740480. Its totient is φ = 259850112.

The previous prime is 649625423. The next prime is 649625441. The reversal of 649625440 is 44526946.

It is a happy number.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 649625393 and 649625402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649625441) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2029920 + ... + 2030239.

It is an arithmetic number, because the mean of its divisors is an integer number (63947520).

Almost surely, 2^649625440 is an apocalyptic number.

It is an amenable number.

649625440 is an abundant number, since it is smaller than the sum of its proper divisors (885115040).

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

649625440 is a wasteful number, since it uses less digits than its factorization.

649625440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4060174 (or 4060166 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 40.

The square root of 649625440 is about 25487.7507834646. The cubic root of 649625440 is about 866.0726843861.

The spelling of 649625440 in words is "six hundred forty-nine million, six hundred twenty-five thousand, four hundred forty".