81203180 has 12 divisors (see below), whose sum is σ = 170526720. Its totient is φ = 32481264.

The previous prime is 81203173. The next prime is 81203257. The reversal of 81203180 is 8130218.

It is a super-2 number, since 2×81203180² = 13187912884224800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2030060 + ... + 2030099.

It is an arithmetic number, because the mean of its divisors is an integer number (14210560).

Almost surely, 2^81203180 is an apocalyptic number.

It is an amenable number.

81203180 is an abundant number, since it is smaller than the sum of its proper divisors (89323540).

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

81203180 is a wasteful number, since it uses less digits than its factorization.

81203180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4060168 (or 4060166 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 81203180 is about 9011.2807080903. The cubic root of 81203180 is about 433.0363421930.

Adding to 81203180 its reverse (8130218), we get a palindrome (89333398).

The spelling of 81203180 in words is "eighty-one million, two hundred three thousand, one hundred eighty".