81841464 has 48 divisors (see below), whose sum is σ = 223371720. Its totient is φ = 27069120.

The previous prime is 81841439. The next prime is 81841469. The reversal of 81841464 is 46414818.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81841469) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5094 + ... + 13770.

Almost surely, 2^81841464 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81841464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111685860).

81841464 is an abundant number, since it is smaller than the sum of its proper divisors (141530256).

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

81841464 is a wasteful number, since it uses less digits than its factorization.

81841464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8820 (or 8813 counting only the distinct ones).

The product of its digits is 24576, while the sum is 36.

The square root of 81841464 is about 9046.6272168140. The cubic root of 81841464 is about 434.1679855415.

The spelling of 81841464 in words is "eighty-one million, eight hundred forty-one thousand, four hundred sixty-four".