181009494 has 48 divisors (see below), whose sum is σ = 410623200. Its totient is φ = 57518208.

The previous prime is 181009483. The next prime is 181009501. The reversal of 181009494 is 494900181.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 168792 + ... + 169860.

It is an arithmetic number, because the mean of its divisors is an integer number (8554650).

Almost surely, 2^181009494 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 181009494, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (205311600).

181009494 is an abundant number, since it is smaller than the sum of its proper divisors (229613706).

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

181009494 is a wasteful number, since it uses less digits than its factorization.

181009494 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1509 (or 1506 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 181009494 is about 13453.9768841781. The cubic root of 181009494 is about 565.6751726970.

It can be divided in two parts, 181009 and 494, that added together give a triangular number (181503 = T₆₀₂).

The spelling of 181009494 in words is "one hundred eighty-one million, nine thousand, four hundred ninety-four".