20389660 has 24 divisors (see below), whose sum is σ = 45072720. Its totient is φ = 7726464.

The previous prime is 20389657. The next prime is 20389667. The reversal of 20389660 is 6698302.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20389667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26449 + ... + 27208.

It is an arithmetic number, because the mean of its divisors is an integer number (1878030).

Almost surely, 2^20389660 is an apocalyptic number.

20389660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20389660 is an abundant number, since it is smaller than the sum of its proper divisors (24683060).

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

20389660 is a wasteful number, since it uses less digits than its factorization.

20389660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53685 (or 53683 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 20389660 is about 4515.4911139321. The cubic root of 20389660 is about 273.1932688430.

The spelling of 20389660 in words is "twenty million, three hundred eighty-nine thousand, six hundred sixty".