20055491 has 2 divisors, whose sum is σ = 20055492. Its totient is φ = 20055490.

The previous prime is 20055487. The next prime is 20055547. The reversal of 20055491 is 19455002.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20055491 - 2² = 20055487 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 20055491.

It is not a weakly prime, because it can be changed into another prime (20055391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10027745 + 10027746.

It is an arithmetic number, because the mean of its divisors is an integer number (10027746).

Almost surely, 2^20055491 is an apocalyptic number.

20055491 is a deficient number, since it is larger than the sum of its proper divisors (1).

20055491 is an equidigital number, since it uses as much as digits as its factorization.

20055491 is an evil number, because the sum of its binary digits is even.

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

The square root of 20055491 is about 4478.3357399820. The cubic root of 20055491 is about 271.6925727529.

The spelling of 20055491 in words is "twenty million, fifty-five thousand, four hundred ninety-one".