181956404 has 72 divisors (see below), whose sum is σ = 390394368. Its totient is φ = 73846080.

The previous prime is 181956403. The next prime is 181956431. The reversal of 181956404 is 404659181.

It is a super-2 number, since 2×181956404² = 66216265913222432, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181956403) 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, 815837 + ... + 816059.

It is an arithmetic number, because the mean of its divisors is an integer number (5422144).

Almost surely, 2^181956404 is an apocalyptic number.

181956404 is a gapful number since it is divisible by the number (14) 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 181956404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (195197184).

181956404 is an abundant number, since it is smaller than the sum of its proper divisors (208437964).

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

181956404 is a wasteful number, since it uses less digits than its factorization.

181956404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 445 (or 436 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 181956404 is about 13489.1216911999. The cubic root of 181956404 is about 566.6598579728.

The spelling of 181956404 in words is "one hundred eighty-one million, nine hundred fifty-six thousand, four hundred four".