20890447 has 2 divisors, whose sum is σ = 20890448. Its totient is φ = 20890446.

The previous prime is 20890409. The next prime is 20890453. The reversal of 20890447 is 74409802.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20890447 - 2¹⁵ = 20857679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20891447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10445223 + 10445224.

It is an arithmetic number, because the mean of its divisors is an integer number (10445224).

Almost surely, 2^20890447 is an apocalyptic number.

20890447 is a deficient number, since it is larger than the sum of its proper divisors (1).

20890447 is an equidigital number, since it uses as much as digits as its factorization.

20890447 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 20890447 is about 4570.6068524869. The cubic root of 20890447 is about 275.4118215433.

The spelling of 20890447 in words is "twenty million, eight hundred ninety thousand, four hundred forty-seven".