39697664 has 18 divisors (see below), whose sum is σ = 79240770. Its totient is φ = 19848704.

The previous prime is 39697663. The next prime is 39697687. The reversal of 39697664 is 46679693.

It can be written as a sum of positive squares in only one way, i.e., 33547264 + 6150400 = 5792^2 + 2480^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39697663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77279 + ... + 77790.

It is an arithmetic number, because the mean of its divisors is an integer number (4402265).

Almost surely, 2^39697664 is an apocalyptic number.

It is an amenable number.

39697664 is a deficient number, since it is larger than the sum of its proper divisors (39543106).

39697664 is an equidigital number, since it uses as much as digits as its factorization.

39697664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155085 (or 155071 counting only the distinct ones).

The product of its digits is 1469664, while the sum is 50.

The square root of 39697664 is about 6300.6082246082. The cubic root of 39697664 is about 341.1313638066.

The spelling of 39697664 in words is "thirty-nine million, six hundred ninety-seven thousand, six hundred sixty-four".