16921187 has 2 divisors, whose sum is σ = 16921188. Its totient is φ = 16921186.

The previous prime is 16921183. The next prime is 16921279. The reversal of 16921187 is 78112961.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16921187 - 2² = 16921183 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16921183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8460593 + 8460594.

It is an arithmetic number, because the mean of its divisors is an integer number (8460594).

Almost surely, 2^16921187 is an apocalyptic number.

16921187 is a deficient number, since it is larger than the sum of its proper divisors (1).

16921187 is an equidigital number, since it uses as much as digits as its factorization.

16921187 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6048, while the sum is 35.

The square root of 16921187 is about 4113.5370424976. The cubic root of 16921187 is about 256.7301896707.

The spelling of 16921187 in words is "sixteen million, nine hundred twenty-one thousand, one hundred eighty-seven".