20841989 has 8 divisors (see below), whose sum is σ = 24463488. Its totient is φ = 17381520.

The previous prime is 20841973. The next prime is 20842007. The reversal of 20841989 is 98914802.

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 20841989 - 2⁴ = 20841973 is a prime.

It is a super-2 number, since 2×20841989² = 868777010952242, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20841959) 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, 39977 + ... + 40494.

It is an arithmetic number, because the mean of its divisors is an integer number (3057936).

Almost surely, 2^20841989 is an apocalyptic number.

It is an amenable number.

20841989 is a deficient number, since it is larger than the sum of its proper divisors (3621499).

20841989 is an equidigital number, since it uses as much as digits as its factorization.

20841989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80515.

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 20841989 is about 4565.3027281879. The cubic root of 20841989 is about 275.1987059738.

The spelling of 20841989 in words is "twenty million, eight hundred forty-one thousand, nine hundred eighty-nine".