39779021 has 4 divisors (see below), whose sum is σ = 40189212. Its totient is φ = 39368832.

The previous prime is 39779017. The next prime is 39779041. The reversal of 39779021 is 12097793.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14668900 + 25110121 = 3830^2 + 5011^2 .

It is a cyclic number.

It is not a de Polignac number, because 39779021 - 2² = 39779017 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 (39779041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 204950 + ... + 205143.

It is an arithmetic number, because the mean of its divisors is an integer number (10047303).

Almost surely, 2^39779021 is an apocalyptic number.

It is an amenable number.

39779021 is a deficient number, since it is larger than the sum of its proper divisors (410191).

39779021 is an equidigital number, since it uses as much as digits as its factorization.

39779021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410190.

The product of its (nonzero) digits is 23814, while the sum is 38.

The square root of 39779021 is about 6307.0612015423. The cubic root of 39779021 is about 341.3642447346.

The spelling of 39779021 in words is "thirty-nine million, seven hundred seventy-nine thousand, twenty-one".