39940861 has 4 divisors (see below), whose sum is σ = 40120192. Its totient is φ = 39761532.

The previous prime is 39940841. The next prime is 39940897. The reversal of 39940861 is 16804993.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 39940861 - 2²¹ = 37843709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39940841) 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, 89331 + ... + 89776.

It is an arithmetic number, because the mean of its divisors is an integer number (10030048).

Almost surely, 2^39940861 is an apocalyptic number.

It is an amenable number.

39940861 is a deficient number, since it is larger than the sum of its proper divisors (179331).

39940861 is a wasteful number, since it uses less digits than its factorization.

39940861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179330.

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 39940861 is about 6319.8782424980. The cubic root of 39940861 is about 341.8265624253.

It can be divided in two parts, 39 and 940861, that added together give a square (940900 = 970²).

The spelling of 39940861 in words is "thirty-nine million, nine hundred forty thousand, eight hundred sixty-one".