81758707 has 2 divisors, whose sum is σ = 81758708. Its totient is φ = 81758706.

The previous prime is 81758669. The next prime is 81758711. The reversal of 81758707 is 70785718.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81758707 is a prime.

It is not a weakly prime, because it can be changed into another prime (81758407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40879353 + 40879354.

It is an arithmetic number, because the mean of its divisors is an integer number (40879354).

Almost surely, 2^81758707 is an apocalyptic number.

81758707 is a deficient number, since it is larger than the sum of its proper divisors (1).

81758707 is an equidigital number, since it uses as much as digits as its factorization.

81758707 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 109760, while the sum is 43.

The square root of 81758707 is about 9042.0521453927. The cubic root of 81758707 is about 434.0215945565.

The spelling of 81758707 in words is "eighty-one million, seven hundred fifty-eight thousand, seven hundred seven".