20190491 has 6 divisors (see below), whose sum is σ = 20696676. Its totient is φ = 19696400.

The previous prime is 20190487. The next prime is 20190523. The reversal of 20190491 is 19409102.

It is not a de Polignac number, because 20190491 - 2² = 20190487 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 20190491.

It is not an unprimeable number, because it can be changed into a prime (20190421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4325 + ... + 7686.

It is an arithmetic number, because the mean of its divisors is an integer number (3449446).

Almost surely, 2^20190491 is an apocalyptic number.

20190491 is a deficient number, since it is larger than the sum of its proper divisors (506185).

20190491 is an equidigital number, since it uses as much as digits as its factorization.

20190491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12093 (or 12052 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 20190491 is about 4493.3830239587. The cubic root of 20190491 is about 272.3008268787.

Adding to 20190491 its reverse (19409102), we get a palindrome (39599593).

The spelling of 20190491 in words is "twenty million, one hundred ninety thousand, four hundred ninety-one".