81413207 has 2 divisors, whose sum is σ = 81413208. Its totient is φ = 81413206.

The previous prime is 81413203. The next prime is 81413219. The reversal of 81413207 is 70231418.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81413207 - 2² = 81413203 is a prime.

It is a super-2 number, since 2×81413207² = 13256220548049698, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81413203) 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, 40706603 + 40706604.

It is an arithmetic number, because the mean of its divisors is an integer number (40706604).

Almost surely, 2^81413207 is an apocalyptic number.

81413207 is a deficient number, since it is larger than the sum of its proper divisors (1).

81413207 is an equidigital number, since it uses as much as digits as its factorization.

81413207 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 81413207 is about 9022.9267424711. The cubic root of 81413207 is about 433.4093613479.

The spelling of 81413207 in words is "eighty-one million, four hundred thirteen thousand, two hundred seven".