20389680 has 60 divisors (see below), whose sum is σ = 68477760. Its totient is φ = 5437056.

The previous prime is 20389667. The next prime is 20389727. The reversal of 20389680 is 8698302.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (36).

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 11 ways as a sum of consecutive naturals, for example, 13440 + ... + 14879.

It is an arithmetic number, because the mean of its divisors is an integer number (1141296).

Almost surely, 2^20389680 is an apocalyptic number.

20389680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20389680 is an abundant number, since it is smaller than the sum of its proper divisors (48088080).

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

20389680 is a wasteful number, since it uses less digits than its factorization.

20389680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28338 (or 28329 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 20389680 is about 4515.4933285301. The cubic root of 20389680 is about 273.1933581671.

The spelling of 20389680 in words is "twenty million, three hundred eighty-nine thousand, six hundred eighty".