81129703 has 2 divisors, whose sum is σ = 81129704. Its totient is φ = 81129702.

The previous prime is 81129679. The next prime is 81129731. The reversal of 81129703 is 30792118.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81129703 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81129793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40564851 + 40564852.

It is an arithmetic number, because the mean of its divisors is an integer number (40564852).

Almost surely, 2^81129703 is an apocalyptic number.

81129703 is a deficient number, since it is larger than the sum of its proper divisors (1).

81129703 is an equidigital number, since it uses as much as digits as its factorization.

81129703 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 81129703 is about 9007.2028399498. The cubic root of 81129703 is about 432.9056912625.

The spelling of 81129703 in words is "eighty-one million, one hundred twenty-nine thousand, seven hundred three".