20289140 has 12 divisors (see below), whose sum is σ = 42607236. Its totient is φ = 8115648.

The previous prime is 20289103. The next prime is 20289167. The reversal of 20289140 is 4198202.

It can be written as a sum of positive squares in 2 ways, for example, as 3429904 + 16859236 = 1852^2 + 4106^2 .

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 507209 + ... + 507248.

It is an arithmetic number, because the mean of its divisors is an integer number (3550603).

Almost surely, 2^20289140 is an apocalyptic number.

20289140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20289140 is an abundant number, since it is smaller than the sum of its proper divisors (22318096).

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

20289140 is a wasteful number, since it uses less digits than its factorization.

20289140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1014466 (or 1014464 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 20289140 is about 4504.3467894912. The cubic root of 20289140 is about 272.7435860276.

The spelling of 20289140 in words is "twenty million, two hundred eighty-nine thousand, one hundred forty".