21610039 has 4 divisors (see below), whose sum is σ = 23574600. Its totient is φ = 19645480.

The previous prime is 21610027. The next prime is 21610067. The reversal of 21610039 is 93001612.

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

It is a cyclic number.

It is not a de Polignac number, because 21610039 - 2⁹ = 21609527 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 (21610019) 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, 982264 + ... + 982285.

It is an arithmetic number, because the mean of its divisors is an integer number (5893650).

Almost surely, 2^21610039 is an apocalyptic number.

21610039 is a deficient number, since it is larger than the sum of its proper divisors (1964561).

21610039 is a wasteful number, since it uses less digits than its factorization.

21610039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1964560.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 21610039 is about 4648.6599144270. The cubic root of 21610039 is about 278.5384686216.

The spelling of 21610039 in words is "twenty-one million, six hundred ten thousand, thirty-nine".