20436140 has 12 divisors (see below), whose sum is σ = 42915936. Its totient is φ = 8174448.

The previous prime is 20436133. The next prime is 20436151. The reversal of 20436140 is 4163402.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1021807 = 20436140 / (2 + 0 + 4 + 3 + 6 + 1 + 4 + 0).

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, 510884 + ... + 510923.

It is an arithmetic number, because the mean of its divisors is an integer number (3576328).

Almost surely, 2^20436140 is an apocalyptic number.

20436140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20436140 is an abundant number, since it is smaller than the sum of its proper divisors (22479796).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20436140 is a wasteful number, since it uses less digits than its factorization.

20436140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1021816 (or 1021814 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 20436140 is about 4520.6349111602. The cubic root of 20436140 is about 273.4007005606.

Adding to 20436140 its reverse (4163402), we get a palindrome (24599542).

The spelling of 20436140 in words is "twenty million, four hundred thirty-six thousand, one hundred forty".