16139621 has 4 divisors (see below), whose sum is σ = 16344000. Its totient is φ = 15935244.

The previous prime is 16139611. The next prime is 16139671. The reversal of 16139621 is 12693161.

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 16139621 - 2¹⁰ = 16138597 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 (16139611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102071 + ... + 102228.

It is an arithmetic number, because the mean of its divisors is an integer number (4086000).

Almost surely, 2^16139621 is an apocalyptic number.

It is an amenable number.

16139621 is a deficient number, since it is larger than the sum of its proper divisors (204379).

16139621 is an equidigital number, since it uses as much as digits as its factorization.

16139621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204378.

The product of its digits is 1944, while the sum is 29.

The square root of 16139621 is about 4017.4147159585. The cubic root of 16139621 is about 252.7150525504.

The spelling of 16139621 in words is "sixteen million, one hundred thirty-nine thousand, six hundred twenty-one".