180420491 has 2 divisors, whose sum is σ = 180420492. Its totient is φ = 180420490.

The previous prime is 180420419. The next prime is 180420509. The reversal of 180420491 is 194024081.

Together with previous prime (180420419) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is an emirp because it is prime and its reverse (194024081) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 180420491 - 2¹⁰ = 180419467 is a prime.

It is not a weakly prime, because it can be changed into another prime (183420491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90210245 + 90210246.

It is an arithmetic number, because the mean of its divisors is an integer number (90210246).

Almost surely, 2^180420491 is an apocalyptic number.

180420491 is a deficient number, since it is larger than the sum of its proper divisors (1).

180420491 is an equidigital number, since it uses as much as digits as its factorization.

180420491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 180420491 is about 13432.0694980334. The cubic root of 180420491 is about 565.0609389462.

The spelling of 180420491 in words is "one hundred eighty million, four hundred twenty thousand, four hundred ninety-one".