81234479 has 2 divisors, whose sum is σ = 81234480. Its totient is φ = 81234478.

The previous prime is 81234431. The next prime is 81234487. The reversal of 81234479 is 97443218.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81234479 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81234409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40617239 + 40617240.

It is an arithmetic number, because the mean of its divisors is an integer number (40617240).

Almost surely, 2^81234479 is an apocalyptic number.

81234479 is a deficient number, since it is larger than the sum of its proper divisors (1).

81234479 is an equidigital number, since it uses as much as digits as its factorization.

81234479 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 38.

The square root of 81234479 is about 9013.0171973652. The cubic root of 81234479 is about 433.0919716379.

The spelling of 81234479 in words is "eighty-one million, two hundred thirty-four thousand, four hundred seventy-nine".