81221862 has 8 divisors (see below), whose sum is σ = 162443736. Its totient is φ = 27073952.

The previous prime is 81221851. The next prime is 81221863. The reversal of 81221862 is 26812218.

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

81221862 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81221863) 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, 6768483 + ... + 6768494.

It is an arithmetic number, because the mean of its divisors is an integer number (20305467).

Almost surely, 2^81221862 is an apocalyptic number.

81221862 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81221862 is a wasteful number, since it uses less digits than its factorization.

81221862 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13536982.

The product of its digits is 3072, while the sum is 30.

The square root of 81221862 is about 9012.3172380914. The cubic root of 81221862 is about 433.0695484649.

The spelling of 81221862 in words is "eighty-one million, two hundred twenty-one thousand, eight hundred sixty-two".