39679021 has 4 divisors (see below), whose sum is σ = 40646844. Its totient is φ = 38711200.

The previous prime is 39678997. The next prime is 39679027. The reversal of 39679021 is 12097693.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12097693 = 17 ⋅711629.

It can be written as a sum of positive squares in 2 ways, for example, as 1102500 + 38576521 = 1050^2 + 6211^2 .

It is a cyclic number.

It is not a de Polignac number, because 39679021 - 2⁷ = 39678893 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 (39679027) 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, 483850 + ... + 483931.

It is an arithmetic number, because the mean of its divisors is an integer number (10161711).

Almost surely, 2^39679021 is an apocalyptic number.

It is an amenable number.

39679021 is a deficient number, since it is larger than the sum of its proper divisors (967823).

39679021 is an equidigital number, since it uses as much as digits as its factorization.

39679021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 967822.

The product of its (nonzero) digits is 20412, while the sum is 37.

The square root of 39679021 is about 6299.1285905274. The cubic root of 39679021 is about 341.0779542169.

The spelling of 39679021 in words is "thirty-nine million, six hundred seventy-nine thousand, twenty-one".