39679621 has 2 divisors, whose sum is σ = 39679622. Its totient is φ = 39679620.

The previous prime is 39679613. The next prime is 39679637. The reversal of 39679621 is 12697693.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25908100 + 13771521 = 5090^2 + 3711^2 .

It is a cyclic number.

It is not a de Polignac number, because 39679621 - 2³ = 39679613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39679681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19839810 + 19839811.

It is an arithmetic number, because the mean of its divisors is an integer number (19839811).

Almost surely, 2^39679621 is an apocalyptic number.

It is an amenable number.

39679621 is a deficient number, since it is larger than the sum of its proper divisors (1).

39679621 is an equidigital number, since it uses as much as digits as its factorization.

39679621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 122472, while the sum is 43.

The square root of 39679621 is about 6299.1762159825. The cubic root of 39679621 is about 341.0796733936.

The spelling of 39679621 in words is "thirty-nine million, six hundred seventy-nine thousand, six hundred twenty-one".