81573622 has 8 divisors (see below), whose sum is σ = 131772816. Its totient is φ = 37649352.

The previous prime is 81573601. The next prime is 81573647. The reversal of 81573622 is 22637518.

It is a happy number.

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

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1568698 + ... + 1568749.

It is an arithmetic number, because the mean of its divisors is an integer number (16471602).

Almost surely, 2^81573622 is an apocalyptic number.

81573622 is a deficient number, since it is larger than the sum of its proper divisors (50199194).

81573622 is a wasteful number, since it uses less digits than its factorization.

81573622 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3137462.

The product of its digits is 20160, while the sum is 34.

The square root of 81573622 is about 9031.8116676556. The cubic root of 81573622 is about 433.6938350484.

The spelling of 81573622 in words is "eighty-one million, five hundred seventy-three thousand, six hundred twenty-two".