20455091 has 2 divisors, whose sum is σ = 20455092. Its totient is φ = 20455090.

The previous prime is 20455087. The next prime is 20455109. The reversal of 20455091 is 19055402.

Together with next prime (20455109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20455091 - 2² = 20455087 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20455091.

It is not a weakly prime, because it can be changed into another prime (20455051) 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 as a sum of consecutive naturals, namely, 10227545 + 10227546.

It is an arithmetic number, because the mean of its divisors is an integer number (10227546).

Almost surely, 2^20455091 is an apocalyptic number.

20455091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20455091 is an equidigital number, since it uses as much as digits as its factorization.

20455091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 20455091 is about 4522.7304805836. The cubic root of 20455091 is about 273.4851851378.

The spelling of 20455091 in words is "twenty million, four hundred fifty-five thousand, ninety-one".