20779928 has 16 divisors (see below), whose sum is σ = 41959680. Its totient is φ = 9590688.

The previous prime is 20779919. The next prime is 20779937. The reversal of 20779928 is 82997702.

It is an interprime number because it is at equal distance from previous prime (20779919) and next prime (20779937).

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99800 + ... + 100007.

It is an arithmetic number, because the mean of its divisors is an integer number (2622480).

Almost surely, 2^20779928 is an apocalyptic number.

It is an amenable number.

20779928 is an abundant number, since it is smaller than the sum of its proper divisors (21179752).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20779928 is a wasteful number, since it uses less digits than its factorization.

20779928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199826 (or 199822 counting only the distinct ones).

The product of its (nonzero) digits is 127008, while the sum is 44.

The square root of 20779928 is about 4558.5006306899. The cubic root of 20779928 is about 274.9252821803.

The spelling of 20779928 in words is "twenty million, seven hundred seventy-nine thousand, nine hundred twenty-eight".