20490843 has 8 divisors (see below), whose sum is σ = 27451456. Its totient is φ = 13595400.

The previous prime is 20490839. The next prime is 20490917. The reversal of 20490843 is 34809402.

It is a happy number.

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

It is not a de Polignac number, because 20490843 - 2² = 20490839 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20490843.

It is not an unprimeable number, because it can be changed into a prime (20490803) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 15553 + ... + 16818.

It is an arithmetic number, because the mean of its divisors is an integer number (3431432).

Almost surely, 2^20490843 is an apocalyptic number.

20490843 is a deficient number, since it is larger than the sum of its proper divisors (6960613).

20490843 is a wasteful number, since it uses less digits than its factorization.

20490843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32585.

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 20490843 is about 4526.6812346354. The cubic root of 20490843 is about 273.6444275046.

The spelling of 20490843 in words is "twenty million, four hundred ninety thousand, eight hundred forty-three".