81222370 has 8 divisors (see below), whose sum is σ = 146200284. Its totient is φ = 32488944.

The previous prime is 81222343. The next prime is 81222371. The reversal of 81222370 is 7322218.

It can be written as a sum of positive squares in 2 ways, for example, as 76055841 + 5166529 = 8721^2 + 2273^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (81222371) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4061109 + ... + 4061128.

Almost surely, 2^81222370 is an apocalyptic number.

81222370 is a deficient number, since it is larger than the sum of its proper divisors (64977914).

81222370 is a wasteful number, since it uses less digits than its factorization.

81222370 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8122244.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 81222370 is about 9012.3454216979. The cubic root of 81222370 is about 433.0704513371.

Adding to 81222370 its reverse (7322218), we get a palindrome (88544588).

The spelling of 81222370 in words is "eighty-one million, two hundred twenty-two thousand, three hundred seventy".