20777123 has 4 divisors (see below), whose sum is σ = 20791320. Its totient is φ = 20762928.

The previous prime is 20777101. The next prime is 20777167. The reversal of 20777123 is 32177702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20777123 - 2⁶ = 20777059 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20777173) 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, 4613 + ... + 7926.

It is an arithmetic number, because the mean of its divisors is an integer number (5197830).

Almost surely, 2^20777123 is an apocalyptic number.

20777123 is a deficient number, since it is larger than the sum of its proper divisors (14197).

20777123 is a wasteful number, since it uses less digits than its factorization.

20777123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14196.

The product of its (nonzero) digits is 4116, while the sum is 29.

The square root of 20777123 is about 4558.1929533533. The cubic root of 20777123 is about 274.9129112661.

The spelling of 20777123 in words is "twenty million, seven hundred seventy-seven thousand, one hundred twenty-three".