20389705 has 8 divisors (see below), whose sum is σ = 27963072. Its totient is φ = 13981488.

The previous prime is 20389667. The next prime is 20389727. The reversal of 20389705 is 50798302.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20389705 - 2¹¹ = 20387657 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 291247 + ... + 291316.

It is an arithmetic number, because the mean of its divisors is an integer number (3495384).

Almost surely, 2^20389705 is an apocalyptic number.

It is an amenable number.

20389705 is a deficient number, since it is larger than the sum of its proper divisors (7573367).

20389705 is an equidigital number, since it uses as much as digits as its factorization.

20389705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 582575.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 20389705 is about 4515.4960967761. The cubic root of 20389705 is about 273.1934698221.

The spelling of 20389705 in words is "twenty million, three hundred eighty-nine thousand, seven hundred five".