81881230 has 16 divisors (see below), whose sum is σ = 152141184. Its totient is φ = 31695840.

The previous prime is 81881221. The next prime is 81881249. The reversal of 81881230 is 3218818.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a junction number, because it is equal to n+sod(n) for n = 81881192 and 81881201.

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, 131757 + ... + 132376.

It is an arithmetic number, because the mean of its divisors is an integer number (9508824).

Almost surely, 2^81881230 is an apocalyptic number.

81881230 is a deficient number, since it is larger than the sum of its proper divisors (70259954).

81881230 is a wasteful number, since it uses less digits than its factorization.

81881230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264171.

The product of its (nonzero) digits is 3072, while the sum is 31.

The square root of 81881230 is about 9048.8247855730. The cubic root of 81881230 is about 434.2382935398.

The spelling of 81881230 in words is "eighty-one million, eight hundred eighty-one thousand, two hundred thirty".