39978693 has 24 divisors (see below), whose sum is σ = 59099040. Its totient is φ = 26036640.

The previous prime is 39978683. The next prime is 39978709. The reversal of 39978693 is 39687993.

It is not a de Polignac number, because 39978693 - 2⁴ = 39978677 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39978683) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 81178 + ... + 81668.

It is an arithmetic number, because the mean of its divisors is an integer number (2462460).

Almost surely, 2^39978693 is an apocalyptic number.

It is an amenable number.

39978693 is a deficient number, since it is larger than the sum of its proper divisors (19120347).

39978693 is a wasteful number, since it uses less digits than its factorization.

39978693 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689 (or 686 counting only the distinct ones).

The product of its digits is 2204496, while the sum is 54.

The square root of 39978693 is about 6322.8706297061. The cubic root of 39978693 is about 341.9344544543.

The spelling of 39978693 in words is "thirty-nine million, nine hundred seventy-eight thousand, six hundred ninety-three".