181620479 has 2 divisors, whose sum is σ = 181620480. Its totient is φ = 181620478.

The previous prime is 181620473. The next prime is 181620497. The reversal of 181620479 is 974026181.

Together with next prime (181620497) 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 181620479 - 2⁸ = 181620223 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181620473) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90810239 + 90810240.

It is an arithmetic number, because the mean of its divisors is an integer number (90810240).

Almost surely, 2^181620479 is an apocalyptic number.

181620479 is a deficient number, since it is larger than the sum of its proper divisors (1).

181620479 is an equidigital number, since it uses as much as digits as its factorization.

181620479 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 181620479 is about 13476.6642386015. The cubic root of 181620479 is about 566.3109236997.

The spelling of 181620479 in words is "one hundred eighty-one million, six hundred twenty thousand, four hundred seventy-nine".