20819140 has 24 divisors (see below), whose sum is σ = 45622080. Its totient is φ = 7965408.

The previous prime is 20819119. The next prime is 20819143. The reversal of 20819140 is 4191802.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20819143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22170 + ... + 23089.

It is an arithmetic number, because the mean of its divisors is an integer number (1900920).

Almost surely, 2^20819140 is an apocalyptic number.

20819140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20819140 is an abundant number, since it is smaller than the sum of its proper divisors (24802940).

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

20819140 is a wasteful number, since it uses less digits than its factorization.

20819140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45291 (or 45289 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 20819140 is about 4562.7995792057. The cubic root of 20819140 is about 275.0981027400.

The spelling of 20819140 in words is "twenty million, eight hundred nineteen thousand, one hundred forty".