20716779 has 8 divisors (see below), whose sum is σ = 27662992. Its totient is φ = 13790880.

The previous prime is 20716769. The next prime is 20716789. The reversal of 20716779 is 97761702.

It is an interprime number because it is at equal distance from previous prime (20716769) and next prime (20716789).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20716779 - 2¹⁵ = 20684011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20716739) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2512 + ... + 6909.

It is an arithmetic number, because the mean of its divisors is an integer number (3457874).

Almost surely, 2^20716779 is an apocalyptic number.

20716779 is a deficient number, since it is larger than the sum of its proper divisors (6946213).

20716779 is an equidigital number, since it uses as much as digits as its factorization.

20716779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10157.

The product of its (nonzero) digits is 37044, while the sum is 39.

The square root of 20716779 is about 4551.5688504075. The cubic root of 20716779 is about 274.6465055805.

The spelling of 20716779 in words is "twenty million, seven hundred sixteen thousand, seven hundred seventy-nine".