81930727 has 2 divisors, whose sum is σ = 81930728. Its totient is φ = 81930726.

The previous prime is 81930721. The next prime is 81930731. The reversal of 81930727 is 72703918.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81930727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81930721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40965363 + 40965364.

It is an arithmetic number, because the mean of its divisors is an integer number (40965364).

Almost surely, 2^81930727 is an apocalyptic number.

81930727 is a deficient number, since it is larger than the sum of its proper divisors (1).

81930727 is an equidigital number, since it uses as much as digits as its factorization.

81930727 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 81930727 is about 9051.5593684182. The cubic root of 81930727 is about 434.3257745712.

The spelling of 81930727 in words is "eighty-one million, nine hundred thirty thousand, seven hundred twenty-seven".