81901222 has 8 divisors (see below), whose sum is σ = 132302016. Its totient is φ = 37800552.

The previous prime is 81901217. The next prime is 81901241. The reversal of 81901222 is 22210918.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1574998 + ... + 1575049.

It is an arithmetic number, because the mean of its divisors is an integer number (16537752).

Almost surely, 2^81901222 is an apocalyptic number.

81901222 is a deficient number, since it is larger than the sum of its proper divisors (50400794).

81901222 is a wasteful number, since it uses less digits than its factorization.

81901222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3150062.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 81901222 is about 9049.9293919898. The cubic root of 81901222 is about 434.2736316571.

The spelling of 81901222 in words is "eighty-one million, nine hundred one thousand, two hundred twenty-two".