81874216 has 16 divisors (see below), whose sum is σ = 153718740. Its totient is φ = 40882560.

The previous prime is 81874189. The next prime is 81874217. The reversal of 81874216 is 61247818.

It can be written as a sum of positive squares in 2 ways, for example, as 81830116 + 44100 = 9046^2 + 210^2 .

It is a super-2 number, since 2×81874216² = 13406774491229312, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81874217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45 + ... + 12796.

Almost surely, 2^81874216 is an apocalyptic number.

It is an amenable number.

81874216 is a deficient number, since it is larger than the sum of its proper divisors (71844524).

81874216 is a wasteful number, since it uses less digits than its factorization.

81874216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13644 (or 13640 counting only the distinct ones).

The product of its digits is 21504, while the sum is 37.

The square root of 81874216 is about 9048.4372131324. The cubic root of 81874216 is about 434.2258941398.

It can be divided in two parts, 8187 and 4216, that added together give a triangular number (12403 = T₁₅₇).

The spelling of 81874216 in words is "eighty-one million, eight hundred seventy-four thousand, two hundred sixteen".