20777959 has 4 divisors (see below), whose sum is σ = 20787480. Its totient is φ = 20768440.

The previous prime is 20777957. The next prime is 20777969. The reversal of 20777959 is 95977702.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20777959 - 2¹ = 20777957 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 (20777951) 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, 324 + ... + 6454.

It is an arithmetic number, because the mean of its divisors is an integer number (5196870).

Almost surely, 2^20777959 is an apocalyptic number.

20777959 is a deficient number, since it is larger than the sum of its proper divisors (9521).

20777959 is an equidigital number, since it uses as much as digits as its factorization.

20777959 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9520.

The product of its (nonzero) digits is 277830, while the sum is 46.

The square root of 20777959 is about 4558.2846554378. The cubic root of 20777959 is about 274.9165984001.

It can be divided in two parts, 20777 and 959, that added together give a triangular number (21736 = T₂₀₈).

The spelling of 20777959 in words is "twenty million, seven hundred seventy-seven thousand, nine hundred fifty-nine".