16491723 has 4 divisors (see below), whose sum is σ = 21988968. Its totient is φ = 10994480.

The previous prime is 16491719. The next prime is 16491731. The reversal of 16491723 is 32719461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32719461 = 3 ⋅10906487.

It is a cyclic number.

It is not a de Polignac number, because 16491723 - 2² = 16491719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16491743) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2748618 + ... + 2748623.

It is an arithmetic number, because the mean of its divisors is an integer number (5497242).

Almost surely, 2^16491723 is an apocalyptic number.

16491723 is a deficient number, since it is larger than the sum of its proper divisors (5497245).

16491723 is an equidigital number, since it uses as much as digits as its factorization.

16491723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5497244.

The product of its digits is 9072, while the sum is 33.

The square root of 16491723 is about 4061.0002462448. Note that the first 3 decimals coincide. The cubic root of 16491723 is about 254.5395921385.

The spelling of 16491723 in words is "sixteen million, four hundred ninety-one thousand, seven hundred twenty-three".