20490427 has 4 divisors (see below), whose sum is σ = 20500816. Its totient is φ = 20480040.

The previous prime is 20490419. The next prime is 20490439. The reversal of 20490427 is 72409402.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20490427 - 2³ = 20490419 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20490395 and 20490404.

It is not an unprimeable number, because it can be changed into a prime (20490497) 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 3 ways as a sum of consecutive naturals, for example, 1224 + ... + 6517.

It is an arithmetic number, because the mean of its divisors is an integer number (5125204).

Almost surely, 2^20490427 is an apocalyptic number.

20490427 is a deficient number, since it is larger than the sum of its proper divisors (10389).

20490427 is an equidigital number, since it uses as much as digits as its factorization.

20490427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10388.

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 20490427 is about 4526.6352846237. The cubic root of 20490427 is about 273.6425756717.

Adding to 20490427 its reverse (72409402), we get a palindrome (92899829).

The spelling of 20490427 in words is "twenty million, four hundred ninety thousand, four hundred twenty-seven".