39649640 has 32 divisors (see below), whose sum is σ = 89397000. Its totient is φ = 15826944.

The previous prime is 39649633. The next prime is 39649657. The reversal of 39649640 is 4694693.

It can be written as a sum of positive squares in 4 ways, for example, as 34975396 + 4674244 = 5914^2 + 2162^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30116 + ... + 31404.

Almost surely, 2^39649640 is an apocalyptic number.

It is an amenable number.

39649640 is an abundant number, since it is smaller than the sum of its proper divisors (49747360).

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

39649640 is a wasteful number, since it uses less digits than its factorization.

39649640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2069 (or 2065 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 41.

The square root of 39649640 is about 6296.7960106708. The cubic root of 39649640 is about 340.9937477892.

The spelling of 39649640 in words is "thirty-nine million, six hundred forty-nine thousand, six hundred forty".