16921451 has 4 divisors (see below), whose sum is σ = 16935600. Its totient is φ = 16907304.

The previous prime is 16921447. The next prime is 16921493. The reversal of 16921451 is 15412961.

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 16921451 - 2² = 16921447 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16921351) 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, 5096 + ... + 7733.

It is an arithmetic number, because the mean of its divisors is an integer number (4233900).

Almost surely, 2^16921451 is an apocalyptic number.

16921451 is a deficient number, since it is larger than the sum of its proper divisors (14149).

16921451 is a wasteful number, since it uses less digits than its factorization.

16921451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14148.

The product of its digits is 2160, while the sum is 29.

The square root of 16921451 is about 4113.5691315450. The cubic root of 16921451 is about 256.7315248099.

The spelling of 16921451 in words is "sixteen million, nine hundred twenty-one thousand, four hundred fifty-one".