81046397 has 2 divisors, whose sum is σ = 81046398. Its totient is φ = 81046396.

The previous prime is 81046379. The next prime is 81046403. The reversal of 81046397 is 79364018.

Together with previous prime (81046379) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53787556 + 27258841 = 7334^2 + 5221^2 .

It is a cyclic number.

It is not a de Polignac number, because 81046397 - 2⁶ = 81046333 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81046397.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81042397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40523198 + 40523199.

It is an arithmetic number, because the mean of its divisors is an integer number (40523199).

Almost surely, 2^81046397 is an apocalyptic number.

It is an amenable number.

81046397 is a deficient number, since it is larger than the sum of its proper divisors (1).

81046397 is an equidigital number, since it uses as much as digits as its factorization.

81046397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 38.

The square root of 81046397 is about 9002.5772421013. The cubic root of 81046397 is about 432.7574677352.

The spelling of 81046397 in words is "eighty-one million, forty-six thousand, three hundred ninety-seven".