16681351 has 4 divisors (see below), whose sum is σ = 17256600. Its totient is φ = 16106104.

The previous prime is 16681337. The next prime is 16681361. The reversal of 16681351 is 15318661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15318661 = 1613 ⋅9497.

It is a cyclic number.

It is not a de Polignac number, because 16681351 - 2⁵ = 16681319 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16681361) 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, 287581 + ... + 287638.

It is an arithmetic number, because the mean of its divisors is an integer number (4314150).

Almost surely, 2^16681351 is an apocalyptic number.

16681351 is a deficient number, since it is larger than the sum of its proper divisors (575249).

16681351 is an equidigital number, since it uses as much as digits as its factorization.

16681351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 575248.

The product of its digits is 4320, while the sum is 31.

The square root of 16681351 is about 4084.2809648701. The cubic root of 16681351 is about 255.5114737310.

The spelling of 16681351 in words is "sixteen million, six hundred eighty-one thousand, three hundred fifty-one".