20206145 has 4 divisors (see below), whose sum is σ = 24247380. Its totient is φ = 16164912.

The previous prime is 20206129. The next prime is 20206169. The reversal of 20206145 is 54160202.

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 10195249 + 10010896 = 3193^2 + 3164^2 .

It is a cyclic number.

It is not a de Polignac number, because 20206145 - 2⁴ = 20206129 is a prime.

It is a super-2 number, since 2×20206145² = 816576591522050, which contains 22 as substring.

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, 2020610 + ... + 2020619.

It is an arithmetic number, because the mean of its divisors is an integer number (6061845).

Almost surely, 2^20206145 is an apocalyptic number.

It is an amenable number.

20206145 is a deficient number, since it is larger than the sum of its proper divisors (4041235).

20206145 is an equidigital number, since it uses as much as digits as its factorization.

20206145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4041234.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 20206145 is about 4495.1245811434. The cubic root of 20206145 is about 272.3711817139.

Adding to 20206145 its reverse (54160202), we get a palindrome (74366347).

The spelling of 20206145 in words is "twenty million, two hundred six thousand, one hundred forty-five".