39857644 has 12 divisors (see below), whose sum is σ = 70894768. Its totient is φ = 19602000.

The previous prime is 39857593. The next prime is 39857647. The reversal of 39857644 is 44675893.

It is a junction number, because it is equal to n+sod(n) for n = 39857594 and 39857603.

It is not an unprimeable number, because it can be changed into a prime (39857647) 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, 81432 + ... + 81919.

Almost surely, 2^39857644 is an apocalyptic number.

It is an amenable number.

39857644 is a deficient number, since it is larger than the sum of its proper divisors (31037124).

39857644 is a wasteful number, since it uses less digits than its factorization.

39857644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163416 (or 163414 counting only the distinct ones).

The product of its digits is 725760, while the sum is 46.

The square root of 39857644 is about 6313.2910593446. The cubic root of 39857644 is about 341.5889981959.

The spelling of 39857644 in words is "thirty-nine million, eight hundred fifty-seven thousand, six hundred forty-four".