20434145 has 4 divisors (see below), whose sum is σ = 24520980. Its totient is φ = 16347312.

The previous prime is 20434109. The next prime is 20434147. The reversal of 20434145 is 54143402.

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 9728161 + 10705984 = 3119^2 + 3272^2 .

It is a cyclic number.

It is not a de Polignac number, because 20434145 - 2⁶ = 20434081 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20434145.

It is not an unprimeable number, because it can be changed into a prime (20434147) 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, 2043410 + ... + 2043419.

It is an arithmetic number, because the mean of its divisors is an integer number (6130245).

Almost surely, 2^20434145 is an apocalyptic number.

It is an amenable number.

20434145 is a deficient number, since it is larger than the sum of its proper divisors (4086835).

20434145 is an equidigital number, since it uses as much as digits as its factorization.

20434145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4086834.

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 20434145 is about 4520.4142509288. The cubic root of 20434145 is about 273.3918037053.

Adding to 20434145 its reverse (54143402), we get a palindrome (74577547).

The spelling of 20434145 in words is "twenty million, four hundred thirty-four thousand, one hundred forty-five".