16506609 has 16 divisors (see below), whose sum is σ = 26633088. Its totient is φ = 8877312.

The previous prime is 16506557. The next prime is 16506619. The reversal of 16506609 is 90660561.

It is not a de Polignac number, because 16506609 - 2⁹ = 16506097 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16506609.

It is not an unprimeable number, because it can be changed into a prime (16506619) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22762 + ... + 23475.

It is an arithmetic number, because the mean of its divisors is an integer number (1664568).

Almost surely, 2^16506609 is an apocalyptic number.

It is an amenable number.

16506609 is a deficient number, since it is larger than the sum of its proper divisors (10126479).

16506609 is a wasteful number, since it uses less digits than its factorization.

16506609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46264.

The product of its (nonzero) digits is 9720, while the sum is 33.

The square root of 16506609 is about 4062.8326325361. The cubic root of 16506609 is about 254.6161545225.

The spelling of 16506609 in words is "sixteen million, five hundred six thousand, six hundred nine".