20204140 has 24 divisors (see below), whose sum is σ = 46286352. Its totient is φ = 7346880.

The previous prime is 20204117. The next prime is 20204147. The reversal of 20204140 is 4140202.

It is a self number, because there is not a number n which added to its sum of digits gives 20204140.

It is not an unprimeable number, because it can be changed into a prime (20204147) 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 7 ways as a sum of consecutive naturals, for example, 45699 + ... + 46138.

It is an arithmetic number, because the mean of its divisors is an integer number (1928598).

Almost surely, 2^20204140 is an apocalyptic number.

20204140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20204140 is an abundant number, since it is smaller than the sum of its proper divisors (26082212).

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

20204140 is a wasteful number, since it uses less digits than its factorization.

20204140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91857 (or 91855 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 20204140 is about 4494.9015562079. The cubic root of 20204140 is about 272.3621725357.

Adding to 20204140 its reverse (4140202), we get a palindrome (24344342).

The spelling of 20204140 in words is "twenty million, two hundred four thousand, one hundred forty".