2181394466 has 8 divisors (see below), whose sum is σ = 3289046124. Its totient is φ = 1085045760.

The previous prime is 2181394447. The next prime is 2181394477. The reversal of 2181394466 is 6644931812.

It can be written as a sum of positive squares in 2 ways, for example, as 1671583225 + 509811241 = 40885^2 + 22579^2 .

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

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, 2825255 + ... + 2826026.

Almost surely, 2^2181394466 is an apocalyptic number.

2181394466 is a deficient number, since it is larger than the sum of its proper divisors (1107651658).

2181394466 is a wasteful number, since it uses less digits than its factorization.

2181394466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5651476.

The product of its digits is 248832, while the sum is 44.

The square root of 2181394466 is about 46705.4008226029. The cubic root of 2181394466 is about 1296.9146686824.

The spelling of 2181394466 in words is "two billion, one hundred eighty-one million, three hundred ninety-four thousand, four hundred sixty-six".