20418229 has 4 divisors (see below), whose sum is σ = 21988876. Its totient is φ = 18847584.

The previous prime is 20418199. The next prime is 20418239. The reversal of 20418229 is 92281402.

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 7851204 + 12567025 = 2802^2 + 3545^2 .

It is a cyclic number.

It is not a de Polignac number, because 20418229 - 2²¹ = 18321077 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20418197 and 20418206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20418239) 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, 785304 + ... + 785329.

It is an arithmetic number, because the mean of its divisors is an integer number (5497219).

Almost surely, 2^20418229 is an apocalyptic number.

It is an amenable number.

20418229 is a deficient number, since it is larger than the sum of its proper divisors (1570647).

20418229 is a wasteful number, since it uses less digits than its factorization.

20418229 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1570646.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 20418229 is about 4518.6534498676. The cubic root of 20418229 is about 273.3208043368.

The spelling of 20418229 in words is "twenty million, four hundred eighteen thousand, two hundred twenty-nine".