81241219 has 2 divisors, whose sum is σ = 81241220. Its totient is φ = 81241218.

The previous prime is 81241211. The next prime is 81241229. The reversal of 81241219 is 91214218.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81241219 - 2³ = 81241211 is a prime.

It is a super-2 number, since 2×81241219² = 13200271329211922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81241211) 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, 40620609 + 40620610.

It is an arithmetic number, because the mean of its divisors is an integer number (40620610).

Almost surely, 2^81241219 is an apocalyptic number.

81241219 is a deficient number, since it is larger than the sum of its proper divisors (1).

81241219 is an equidigital number, since it uses as much as digits as its factorization.

81241219 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 28.

The square root of 81241219 is about 9013.3910932567. The cubic root of 81241219 is about 433.1039491430.

The spelling of 81241219 in words is "eighty-one million, two hundred forty-one thousand, two hundred nineteen".