2181856494 has 8 divisors (see below), whose sum is σ = 4363713000. Its totient is φ = 727285496.

The previous prime is 2181856487. The next prime is 2181856529. The reversal of 2181856494 is 4946581812.

It is a sphenic number, since it is the product of 3 distinct primes.

2181856494 is an admirable number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 181821369 + ... + 181821380.

It is an arithmetic number, because the mean of its divisors is an integer number (545464125).

Almost surely, 2^2181856494 is an apocalyptic number.

2181856494 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

2181856494 is a wasteful number, since it uses less digits than its factorization.

2181856494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363642754.

The product of its digits is 552960, while the sum is 48.

The square root of 2181856494 is about 46710.3467552961. The cubic root of 2181856494 is about 1297.0062261089.

The spelling of 2181856494 in words is "two billion, one hundred eighty-one million, eight hundred fifty-six thousand, four hundred ninety-four".