16691923 has 2 divisors, whose sum is σ = 16691924. Its totient is φ = 16691922.

The previous prime is 16691903. The next prime is 16691957. The reversal of 16691923 is 32919661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16691923 - 2⁵ = 16691891 is a prime.

It is not a weakly prime, because it can be changed into another prime (16691903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8345961 + 8345962.

It is an arithmetic number, because the mean of its divisors is an integer number (8345962).

Almost surely, 2^16691923 is an apocalyptic number.

16691923 is a deficient number, since it is larger than the sum of its proper divisors (1).

16691923 is an equidigital number, since it uses as much as digits as its factorization.

16691923 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17496, while the sum is 37.

The square root of 16691923 is about 4085.5749901330. The cubic root of 16691923 is about 255.5654401204.

The spelling of 16691923 in words is "sixteen million, six hundred ninety-one thousand, nine hundred twenty-three".