20803977 has 6 divisors (see below), whose sum is σ = 30050202. Its totient is φ = 13869312.

The previous prime is 20803961. The next prime is 20803987. The reversal of 20803977 is 77930802.

It can be written as a sum of positive squares in only one way, i.e., 18481401 + 2322576 = 4299^2 + 1524^2 .

It is not a de Polignac number, because 20803977 - 2⁴ = 20803961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20803907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1155768 + ... + 1155785.

It is an arithmetic number, because the mean of its divisors is an integer number (5008367).

Almost surely, 2^20803977 is an apocalyptic number.

It is an amenable number.

20803977 is a deficient number, since it is larger than the sum of its proper divisors (9246225).

20803977 is a wasteful number, since it uses less digits than its factorization.

20803977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2311559 (or 2311556 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 20803977 is about 4561.1376870250. The cubic root of 20803977 is about 275.0313000186.

The spelling of 20803977 in words is "twenty million, eight hundred three thousand, nine hundred seventy-seven".