20385940 has 12 divisors (see below), whose sum is σ = 42810516. Its totient is φ = 8154368.

The previous prime is 20385931. The next prime is 20385971. The reversal of 20385940 is 4958302.

It can be written as a sum of positive squares in 2 ways, for example, as 4112784 + 16273156 = 2028^2 + 4034^2 .

It is a congruent number.

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, 509629 + ... + 509668.

It is an arithmetic number, because the mean of its divisors is an integer number (3567543).

Almost surely, 2^20385940 is an apocalyptic number.

20385940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20385940 is an abundant number, since it is smaller than the sum of its proper divisors (22424576).

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

20385940 is a wasteful number, since it uses less digits than its factorization.

20385940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1019306 (or 1019304 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 20385940 is about 4515.0791798151. The cubic root of 20385940 is about 273.1766535460.

The spelling of 20385940 in words is "twenty million, three hundred eighty-five thousand, nine hundred forty".