81262798 has 4 divisors (see below), whose sum is σ = 121894200. Its totient is φ = 40631398.

The previous prime is 81262793. The next prime is 81262799. The reversal of 81262798 is 89726218.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 89726218 = 2 ⋅44863109.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81262793) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20315698 + ... + 20315701.

It is an arithmetic number, because the mean of its divisors is an integer number (30473550).

Almost surely, 2^81262798 is an apocalyptic number.

81262798 is the 4819-th centered heptagonal number.

81262798 is a deficient number, since it is larger than the sum of its proper divisors (40631402).

81262798 is a wasteful number, since it uses less digits than its factorization.

81262798 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40631401.

The product of its digits is 96768, while the sum is 43.

The square root of 81262798 is about 9014.5880660183. The cubic root of 81262798 is about 433.1422922521.

The spelling of 81262798 in words is "eighty-one million, two hundred sixty-two thousand, seven hundred ninety-eight".