39790821 has 16 divisors (see below), whose sum is σ = 60770304. Its totient is φ = 22686384.

The previous prime is 39790771. The next prime is 39790823. The reversal of 39790821 is 12809793.

It is not a de Polignac number, because 39790821 - 2¹⁰ = 39789797 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 39790821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39790823) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8680 + ... + 12446.

It is an arithmetic number, because the mean of its divisors is an integer number (3798144).

Almost surely, 2^39790821 is an apocalyptic number.

It is an amenable number.

39790821 is a deficient number, since it is larger than the sum of its proper divisors (20979483).

39790821 is a wasteful number, since it uses less digits than its factorization.

39790821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4280.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 39790821 is about 6307.9965916288. The cubic root of 39790821 is about 341.3979953545.

The spelling of 39790821 in words is "thirty-nine million, seven hundred ninety thousand, eight hundred twenty-one".