81838741 has 2 divisors, whose sum is σ = 81838742. Its totient is φ = 81838740.

The previous prime is 81838727. The next prime is 81838751. The reversal of 81838741 is 14783818.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 81270225 + 568516 = 9015^2 + 754^2 .

It is a cyclic number.

It is not a de Polignac number, because 81838741 - 2¹⁵ = 81805973 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 81838694 and 81838703.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81838751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40919370 + 40919371.

It is an arithmetic number, because the mean of its divisors is an integer number (40919371).

Almost surely, 2^81838741 is an apocalyptic number.

It is an amenable number.

81838741 is a deficient number, since it is larger than the sum of its proper divisors (1).

81838741 is an equidigital number, since it uses as much as digits as its factorization.

81838741 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43008, while the sum is 40.

The square root of 81838741 is about 9046.4767174851. The cubic root of 81838741 is about 434.1631703273.

The spelling of 81838741 in words is "eighty-one million, eight hundred thirty-eight thousand, seven hundred forty-one".