81854867 has 2 divisors, whose sum is σ = 81854868. Its totient is φ = 81854866.

The previous prime is 81854837. The next prime is 81854887. The reversal of 81854867 is 76845818.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81854867 - 2⁶ = 81854803 is a prime.

It is not a weakly prime, because it can be changed into another prime (81854807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40927433 + 40927434.

It is an arithmetic number, because the mean of its divisors is an integer number (40927434).

Almost surely, 2^81854867 is an apocalyptic number.

81854867 is a deficient number, since it is larger than the sum of its proper divisors (1).

81854867 is an equidigital number, since it uses as much as digits as its factorization.

81854867 is an evil number, because the sum of its binary digits is even.

The product of its digits is 430080, while the sum is 47.

The square root of 81854867 is about 9047.3679597991. The cubic root of 81854867 is about 434.1916851659.

The spelling of 81854867 in words is "eighty-one million, eight hundred fifty-four thousand, eight hundred sixty-seven".