16940681 has 4 divisors (see below), whose sum is σ = 17155200. Its totient is φ = 16726164.

The previous prime is 16940639. The next prime is 16940689. The reversal of 16940681 is 18604961.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18604961 = 53 ⋅351037.

It is a cyclic number.

It is not a de Polignac number, because 16940681 - 2⁶ = 16940617 is a prime.

It is a super-2 number, since 2×16940681² = 573973345487522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16940689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107141 + ... + 107298.

It is an arithmetic number, because the mean of its divisors is an integer number (4288800).

Almost surely, 2^16940681 is an apocalyptic number.

It is an amenable number.

16940681 is a deficient number, since it is larger than the sum of its proper divisors (214519).

16940681 is an equidigital number, since it uses as much as digits as its factorization.

16940681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214518.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 16940681 is about 4115.9058541225. The cubic root of 16940681 is about 256.8287402366.

The spelling of 16940681 in words is "sixteen million, nine hundred forty thousand, six hundred eighty-one".