81244160 has 52 divisors (see below), whose sum is σ = 195011328. Its totient is φ = 32489472.

The previous prime is 81244147. The next prime is 81244183. The reversal of 81244160 is 6144218.

It is a super-2 number, since 2×81244160² = 13201227068211200, 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, 18497 + ... + 22463.

Almost surely, 2^81244160 is an apocalyptic number.

81244160 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81244160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97505664).

81244160 is an abundant number, since it is smaller than the sum of its proper divisors (113767168).

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

81244160 is an equidigital number, since it uses as much as digits as its factorization.

81244160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3996 (or 3974 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 81244160 is about 9013.5542379241. The cubic root of 81244160 is about 433.1091753216.

Adding to 81244160 its reverse (6144218), we get a palindrome (87388378).

The spelling of 81244160 in words is "eighty-one million, two hundred forty-four thousand, one hundred sixty".