39725981 has 8 divisors (see below), whose sum is σ = 40187904. Its totient is φ = 39266640.

The previous prime is 39725963. The next prime is 39725993. The reversal of 39725981 is 18952793.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-39725981 is a prime.

It is a super-2 number, since 2×39725981² = 3156307132824722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39725921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53096 + ... + 53838.

It is an arithmetic number, because the mean of its divisors is an integer number (5023488).

Almost surely, 2^39725981 is an apocalyptic number.

It is an amenable number.

39725981 is a deficient number, since it is larger than the sum of its proper divisors (461923).

39725981 is a wasteful number, since it uses less digits than its factorization.

39725981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1291.

The product of its digits is 136080, while the sum is 44.

The square root of 39725981 is about 6302.8549880193. The cubic root of 39725981 is about 341.2124560753.

The spelling of 39725981 in words is "thirty-nine million, seven hundred twenty-five thousand, nine hundred eighty-one".