81122418 has 64 divisors (see below), whose sum is σ = 196922880. Its totient is φ = 24603264.

The previous prime is 81122417. The next prime is 81122441. The reversal of 81122418 is 81422118.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 81122391 and 81122400.

It is not an unprimeable number, because it can be changed into a prime (81122411) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 50455 + ... + 52037.

It is an arithmetic number, because the mean of its divisors is an integer number (3076920).

Almost surely, 2^81122418 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81122418, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98461440).

81122418 is an abundant number, since it is smaller than the sum of its proper divisors (115800462).

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

81122418 is a wasteful number, since it uses less digits than its factorization.

81122418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1680 (or 1674 counting only the distinct ones).

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

The square root of 81122418 is about 9006.7984322955. The cubic root of 81122418 is about 432.8927333599.

The spelling of 81122418 in words is "eighty-one million, one hundred twenty-two thousand, four hundred eighteen".