16691285 has 12 divisors (see below), whose sum is σ = 21689892. Its totient is φ = 12325248.

The previous prime is 16691281. The next prime is 16691293. The reversal of 16691285 is 58219661.

It can be written as a sum of positive squares in 6 ways, for example, as 4919524 + 11771761 = 2218^2 + 3431^2 .

It is not a de Polignac number, because 16691285 - 2² = 16691281 is a prime.

It is a super-3 number, since 3×16691285³ (a number of 23 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16691281) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9032 + ... + 10721.

It is an arithmetic number, because the mean of its divisors is an integer number (1807491).

Almost surely, 2^16691285 is an apocalyptic number.

It is an amenable number.

16691285 is a deficient number, since it is larger than the sum of its proper divisors (4998607).

16691285 is a wasteful number, since it uses less digits than its factorization.

16691285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19784 (or 19771 counting only the distinct ones).

The product of its digits is 25920, while the sum is 38.

The square root of 16691285 is about 4085.4969098018. The cubic root of 16691285 is about 255.5621839981.

The spelling of 16691285 in words is "sixteen million, six hundred ninety-one thousand, two hundred eighty-five".