20406434 has 8 divisors (see below), whose sum is σ = 30737388. Its totient is φ = 10160640.

The previous prime is 20406403. The next prime is 20406439. The reversal of 20406434 is 43460402.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 18515809 + 1890625 = 4303^2 + 1375^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (20406439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20687 + ... + 21650.

Almost surely, 2^20406434 is an apocalyptic number.

20406434 is a deficient number, since it is larger than the sum of its proper divisors (10330954).

20406434 is a wasteful number, since it uses less digits than its factorization.

20406434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42580.

The product of its (nonzero) digits is 2304, while the sum is 23.

The square root of 20406434 is about 4517.3481158751. The cubic root of 20406434 is about 273.2681644489.

Adding to 20406434 its reverse (43460402), we get a palindrome (63866836).

The spelling of 20406434 in words is "twenty million, four hundred six thousand, four hundred thirty-four".