81360493 has 2 divisors, whose sum is σ = 81360494. Its totient is φ = 81360492.

The previous prime is 81360481. The next prime is 81360497. The reversal of 81360493 is 39406318.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72131049 + 9229444 = 8493^2 + 3038^2 .

It is a cyclic number.

It is not a de Polignac number, because 81360493 - 2¹³ = 81352301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81360497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40680246 + 40680247.

It is an arithmetic number, because the mean of its divisors is an integer number (40680247).

Almost surely, 2^81360493 is an apocalyptic number.

It is an amenable number.

81360493 is a deficient number, since it is larger than the sum of its proper divisors (1).

81360493 is an equidigital number, since it uses as much as digits as its factorization.

81360493 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 81360493 is about 9020.0051552092. The cubic root of 81360493 is about 433.3157988303.

The spelling of 81360493 in words is "eighty-one million, three hundred sixty thousand, four hundred ninety-three".