39649621 has 4 divisors (see below), whose sum is σ = 43254144. Its totient is φ = 36045100.

The previous prime is 39649613. The next prime is 39649633. The reversal of 39649621 is 12694693.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 39649621 - 2³ = 39649613 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 (39649691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1802245 + ... + 1802266.

It is an arithmetic number, because the mean of its divisors is an integer number (10813536).

Almost surely, 2^39649621 is an apocalyptic number.

It is an amenable number.

39649621 is a deficient number, since it is larger than the sum of its proper divisors (3604523).

39649621 is a wasteful number, since it uses less digits than its factorization.

39649621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3604522.

The product of its digits is 69984, while the sum is 40.

The square root of 39649621 is about 6296.7945019669. The cubic root of 39649621 is about 340.9936933214.

The spelling of 39649621 in words is "thirty-nine million, six hundred forty-nine thousand, six hundred twenty-one".