20657045 has 4 divisors (see below), whose sum is σ = 24788460. Its totient is φ = 16525632.

The previous prime is 20657041. The next prime is 20657051. The reversal of 20657045 is 54075602.

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 3301489 + 17355556 = 1817^2 + 4166^2 .

It is a cyclic number.

It is not a de Polignac number, because 20657045 - 2² = 20657041 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20656999 and 20657017.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20657041) 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, 2065700 + ... + 2065709.

It is an arithmetic number, because the mean of its divisors is an integer number (6197115).

Almost surely, 2^20657045 is an apocalyptic number.

It is an amenable number.

20657045 is a deficient number, since it is larger than the sum of its proper divisors (4131415).

20657045 is an equidigital number, since it uses as much as digits as its factorization.

20657045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4131414.

The product of its (nonzero) digits is 8400, while the sum is 29.

The square root of 20657045 is about 4545.0022002195. The cubic root of 20657045 is about 274.3822829172.

The spelling of 20657045 in words is "twenty million, six hundred fifty-seven thousand, forty-five".