16939779 has 4 divisors (see below), whose sum is σ = 22586376. Its totient is φ = 11293184.

The previous prime is 16939771. The next prime is 16939801. The reversal of 16939779 is 97793961.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97793961 = 3 ⋅32597987.

It is a cyclic number.

It is not a de Polignac number, because 16939779 - 2³ = 16939771 is a prime.

It is a super-2 number, since 2×16939779² = 573912225137682, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (16939771) 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, 2823294 + ... + 2823299.

It is an arithmetic number, because the mean of its divisors is an integer number (5646594).

Almost surely, 2^16939779 is an apocalyptic number.

16939779 is a deficient number, since it is larger than the sum of its proper divisors (5646597).

16939779 is an equidigital number, since it uses as much as digits as its factorization.

16939779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5646596.

The product of its digits is 642978, while the sum is 51.

The square root of 16939779 is about 4115.7962777572. The cubic root of 16939779 is about 256.8241819068.

The spelling of 16939779 in words is "sixteen million, nine hundred thirty-nine thousand, seven hundred seventy-nine".