81563222 has 16 divisors (see below), whose sum is σ = 133918512. Its totient is φ = 37026720.

The previous prime is 81563213. The next prime is 81563231. The reversal of 81563222 is 22236518.

It is an interprime number because it is at equal distance from previous prime (81563213) and next prime (81563231).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24128 + ... + 27299.

It is an arithmetic number, because the mean of its divisors is an integer number (8369907).

Almost surely, 2^81563222 is an apocalyptic number.

81563222 is a deficient number, since it is larger than the sum of its proper divisors (52355290).

81563222 is a wasteful number, since it uses less digits than its factorization.

81563222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51503.

The product of its digits is 5760, while the sum is 29.

The square root of 81563222 is about 9031.2359065634. The cubic root of 81563222 is about 433.6754034057.

The spelling of 81563222 in words is "eighty-one million, five hundred sixty-three thousand, two hundred twenty-two".