81927847 has 2 divisors, whose sum is σ = 81927848. Its totient is φ = 81927846.

The previous prime is 81927841. The next prime is 81927883. The reversal of 81927847 is 74872918.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81927847 is a prime.

It is a super-2 number, since 2×81927847² = 13424344228110818, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81927797 and 81927806.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81927841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40963923 + 40963924.

It is an arithmetic number, because the mean of its divisors is an integer number (40963924).

Almost surely, 2^81927847 is an apocalyptic number.

81927847 is a deficient number, since it is larger than the sum of its proper divisors (1).

81927847 is an equidigital number, since it uses as much as digits as its factorization.

81927847 is an evil number, because the sum of its binary digits is even.

The product of its digits is 225792, while the sum is 46.

The square root of 81927847 is about 9051.4002784100. The cubic root of 81927847 is about 434.3206854227.

The spelling of 81927847 in words is "eighty-one million, nine hundred twenty-seven thousand, eight hundred forty-seven".