81214224 has 80 divisors (see below), whose sum is σ = 258233472. Its totient is φ = 21417984.

The previous prime is 81214213. The next prime is 81214279. The reversal of 81214224 is 42241218.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 81214194 and 81214203.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4929 + ... + 13664.

Almost surely, 2^81214224 is an apocalyptic number.

81214224 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

81214224 is an abundant number, since it is smaller than the sum of its proper divisors (177019248).

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

81214224 is a wasteful number, since it uses less digits than its factorization.

81214224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18624 (or 18618 counting only the distinct ones).

The product of its digits is 1024, while the sum is 24.

The square root of 81214224 is about 9011.8934747366. The cubic root of 81214224 is about 433.0559729373.

The spelling of 81214224 in words is "eighty-one million, two hundred fourteen thousand, two hundred twenty-four".