20773645 has 4 divisors (see below), whose sum is σ = 24928380. Its totient is φ = 16618912.

The previous prime is 20773637. The next prime is 20773651. The reversal of 20773645 is 54637702.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 7856809 + 12916836 = 2803^2 + 3594^2 .

It is a cyclic number.

It is not a de Polignac number, because 20773645 - 2³ = 20773637 is a prime.

It is a super-3 number, since 3×20773645³ (a number of 23 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20773645.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2077360 + ... + 2077369.

It is an arithmetic number, because the mean of its divisors is an integer number (6232095).

Almost surely, 2^20773645 is an apocalyptic number.

It is an amenable number.

20773645 is a deficient number, since it is larger than the sum of its proper divisors (4154735).

20773645 is an equidigital number, since it uses as much as digits as its factorization.

20773645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4154734.

The product of its (nonzero) digits is 35280, while the sum is 34.

The square root of 20773645 is about 4557.8114265511. The cubic root of 20773645 is about 274.8975706683.

The spelling of 20773645 in words is "twenty million, seven hundred seventy-three thousand, six hundred forty-five".