81264893 has 2 divisors, whose sum is σ = 81264894. Its totient is φ = 81264892.

The previous prime is 81264877. The next prime is 81264899. The reversal of 81264893 is 39846218.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49308484 + 31956409 = 7022^2 + 5653^2 .

It is a cyclic number.

It is not a de Polignac number, because 81264893 - 2⁴ = 81264877 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81264893.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81264899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40632446 + 40632447.

It is an arithmetic number, because the mean of its divisors is an integer number (40632447).

Almost surely, 2^81264893 is an apocalyptic number.

It is an amenable number.

81264893 is a deficient number, since it is larger than the sum of its proper divisors (1).

81264893 is an equidigital number, since it uses as much as digits as its factorization.

81264893 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82944, while the sum is 41.

The square root of 81264893 is about 9014.7042658093. The cubic root of 81264893 is about 433.1460144363.

The spelling of 81264893 in words is "eighty-one million, two hundred sixty-four thousand, eight hundred ninety-three".