39866991 has 8 divisors (see below), whose sum is σ = 53185200. Its totient is φ = 26563392.

The previous prime is 39866969. The next prime is 39866993. The reversal of 39866991 is 19966893.

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

It is not a de Polignac number, because 39866991 - 2¹³ = 39858799 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39866993) 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, 8421 + ... + 12273.

It is an arithmetic number, because the mean of its divisors is an integer number (6648150).

Almost surely, 2^39866991 is an apocalyptic number.

39866991 is a deficient number, since it is larger than the sum of its proper divisors (13318209).

39866991 is a wasteful number, since it uses less digits than its factorization.

39866991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7305.

The product of its digits is 629856, while the sum is 51.

The square root of 39866991 is about 6314.0312796184. The cubic root of 39866991 is about 341.6156980749.

The spelling of 39866991 in words is "thirty-nine million, eight hundred sixty-six thousand, nine hundred ninety-one".