20890619 has 2 divisors, whose sum is σ = 20890620. Its totient is φ = 20890618.

The previous prime is 20890591. The next prime is 20890663. The reversal of 20890619 is 91609802.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20890619 is a prime.

It is a super-2 number, since 2×20890619² = 872835924406322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20890669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10445309 + 10445310.

It is an arithmetic number, because the mean of its divisors is an integer number (10445310).

Almost surely, 2^20890619 is an apocalyptic number.

20890619 is a deficient number, since it is larger than the sum of its proper divisors (1).

20890619 is an equidigital number, since it uses as much as digits as its factorization.

20890619 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 20890619 is about 4570.6256683303. The cubic root of 20890619 is about 275.4125774024.

The spelling of 20890619 in words is "twenty million, eight hundred ninety thousand, six hundred nineteen".