20889247 has 4 divisors (see below), whose sum is σ = 20920960. Its totient is φ = 20857536.

The previous prime is 20889233. The next prime is 20889269. The reversal of 20889247 is 74298802.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20889247 - 2²³ = 12500639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20889347) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14847 + ... + 16192.

It is an arithmetic number, because the mean of its divisors is an integer number (5230240).

Almost surely, 2^20889247 is an apocalyptic number.

20889247 is a deficient number, since it is larger than the sum of its proper divisors (31713).

20889247 is an equidigital number, since it uses as much as digits as its factorization.

20889247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31712.

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 20889247 is about 4570.4755770051. The cubic root of 20889247 is about 275.4065479923.

The spelling of 20889247 in words is "twenty million, eight hundred eighty-nine thousand, two hundred forty-seven".