20409436 has 6 divisors (see below), whose sum is σ = 35716520. Its totient is φ = 10204716.

The previous prime is 20409383. The next prime is 20409437. The reversal of 20409436 is 63490402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20409437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2551176 + ... + 2551183.

Almost surely, 2^20409436 is an apocalyptic number.

It is an amenable number.

20409436 is a deficient number, since it is larger than the sum of its proper divisors (15307084).

20409436 is a wasteful number, since it uses less digits than its factorization.

20409436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5102363 (or 5102361 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 20409436 is about 4517.6803782472. The cubic root of 20409436 is about 273.2815639942.

Adding to 20409436 its reverse (63490402), we get a palindrome (83899838).

It can be divided in two parts, 2040 and 9436, that added together give a triangular number (11476 = T₁₅₁).

The spelling of 20409436 in words is "twenty million, four hundred nine thousand, four hundred thirty-six".