81817322 has 4 divisors (see below), whose sum is σ = 122725986. Its totient is φ = 40908660.

The previous prime is 81817313. The next prime is 81817327. The reversal of 81817322 is 22371818.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 51136801 + 30680521 = 7151^2 + 5539^2 .

It is not an unprimeable number, because it can be changed into a prime (81817327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20454329 + ... + 20454332.

Almost surely, 2^81817322 is an apocalyptic number.

81817322 is a deficient number, since it is larger than the sum of its proper divisors (40908664).

81817322 is a wasteful number, since it uses less digits than its factorization.

81817322 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40908663.

The product of its digits is 5376, while the sum is 32.

The square root of 81817322 is about 9045.2928089698. The cubic root of 81817322 is about 434.1252903362.

The spelling of 81817322 in words is "eighty-one million, eight hundred seventeen thousand, three hundred twenty-two".