16351621 has 16 divisors (see below), whose sum is σ = 19877760. Its totient is φ = 13245120.

The previous prime is 16351589. The next prime is 16351627. The reversal of 16351621 is 12615361.

It is a cyclic number.

It is not a de Polignac number, because 16351621 - 2⁵ = 16351589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16351627) 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 15 ways as a sum of consecutive naturals, for example, 2176 + ... + 6118.

It is an arithmetic number, because the mean of its divisors is an integer number (1242360).

Almost surely, 2^16351621 is an apocalyptic number.

16351621 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16351621 is a deficient number, since it is larger than the sum of its proper divisors (3526139).

16351621 is a wasteful number, since it uses less digits than its factorization.

16351621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3996.

The product of its digits is 1080, while the sum is 25.

The square root of 16351621 is about 4043.7137633616. The cubic root of 16351621 is about 253.8167452851.

Adding to 16351621 its reverse (12615361), we get a palindrome (28966982).

The spelling of 16351621 in words is "sixteen million, three hundred fifty-one thousand, six hundred twenty-one".