81224851 has 8 divisors (see below), whose sum is σ = 82059264. Its totient is φ = 80395080.

The previous prime is 81224839. The next prime is 81224881. The reversal of 81224851 is 15842218.

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

It is a cyclic number.

It is not a de Polignac number, because 81224851 - 2⁷ = 81224723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81224881) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41640 + ... + 43546.

It is an arithmetic number, because the mean of its divisors is an integer number (10257408).

Almost surely, 2^81224851 is an apocalyptic number.

81224851 is a deficient number, since it is larger than the sum of its proper divisors (834413).

81224851 is a wasteful number, since it uses less digits than its factorization.

81224851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2321.

The product of its digits is 5120, while the sum is 31.

The square root of 81224851 is about 9012.4830651713. The cubic root of 81224851 is about 433.0748607826.

The spelling of 81224851 in words is "eighty-one million, two hundred twenty-four thousand, eight hundred fifty-one".