81926057 has 2 divisors, whose sum is σ = 81926058. Its totient is φ = 81926056.

The previous prime is 81926041. The next prime is 81926083. The reversal of 81926057 is 75062918.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81342361 + 583696 = 9019^2 + 764^2 .

It is a cyclic number.

It is not a de Polignac number, because 81926057 - 2⁴ = 81926041 is a prime.

It is a Chen prime.

It is equal to p_4775339 and since 81926057 and 4775339 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81926057.

It is not a weakly prime, because it can be changed into another prime (81926657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40963028 + 40963029.

It is an arithmetic number, because the mean of its divisors is an integer number (40963029).

Almost surely, 2^81926057 is an apocalyptic number.

It is an amenable number.

81926057 is a deficient number, since it is larger than the sum of its proper divisors (1).

81926057 is an equidigital number, since it uses as much as digits as its factorization.

81926057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 81926057 is about 9051.3013981416. The cubic root of 81926057 is about 434.3175223155.

The spelling of 81926057 in words is "eighty-one million, nine hundred twenty-six thousand, fifty-seven".