81401418 has 48 divisors (see below), whose sum is σ = 203448960. Its totient is φ = 23040288.

The previous prime is 81401413. The next prime is 81401431. The reversal of 81401418 is 81410418.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 81401391 and 81401400.

It is not an unprimeable number, because it can be changed into a prime (81401413) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10771 + ... + 16697.

It is an arithmetic number, because the mean of its divisors is an integer number (4238520).

Almost surely, 2^81401418 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81401418, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101724480).

81401418 is an abundant number, since it is smaller than the sum of its proper divisors (122047542).

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

81401418 is a wasteful number, since it uses less digits than its factorization.

81401418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6051 (or 6048 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 27.

The square root of 81401418 is about 9022.2734385519. The cubic root of 81401418 is about 433.3884404605.

The spelling of 81401418 in words is "eighty-one million, four hundred one thousand, four hundred eighteen".