16491905 has 8 divisors (see below), whose sum is σ = 20832000. Its totient is φ = 12499056.

The previous prime is 16491889. The next prime is 16491911. The reversal of 16491905 is 50919461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 16491905 - 2⁴ = 16491889 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86705 + ... + 86894.

It is an arithmetic number, because the mean of its divisors is an integer number (2604000).

Almost surely, 2^16491905 is an apocalyptic number.

It is an amenable number.

16491905 is a deficient number, since it is larger than the sum of its proper divisors (4340095).

16491905 is a wasteful number, since it uses less digits than its factorization.

16491905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173623.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 16491905 is about 4061.0226544554. The cubic root of 16491905 is about 254.5405284877.

The spelling of 16491905 in words is "sixteen million, four hundred ninety-one thousand, nine hundred five".