20773989 has 10 divisors (see below), whose sum is σ = 31032870. Its totient is φ = 13849272.

The previous prime is 20773979. The next prime is 20773997. The reversal of 20773989 is 98937702.

It can be written as a sum of positive squares in only one way, i.e., 20657025 + 116964 = 4545^2 + 342^2 .

It is not a de Polignac number, because 20773989 - 2¹⁶ = 20708453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20773939) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 128154 + ... + 128315.

It is an arithmetic number, because the mean of its divisors is an integer number (3103287).

Almost surely, 2^20773989 is an apocalyptic number.

It is an amenable number.

20773989 is a deficient number, since it is larger than the sum of its proper divisors (10258881).

20773989 is an equidigital number, since it uses as much as digits as its factorization.

20773989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 256481 (or 256472 counting only the distinct ones).

The product of its (nonzero) digits is 190512, while the sum is 45.

The square root of 20773989 is about 4557.8491638052. The cubic root of 20773989 is about 274.8990880435.

The spelling of 20773989 in words is "twenty million, seven hundred seventy-three thousand, nine hundred eighty-nine".