2178938851 has 8 divisors (see below), whose sum is σ = 2220253200. Its totient is φ = 2137998720.

The previous prime is 2178938837. The next prime is 2178938863. The reversal of 2178938851 is 1588398712.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 2178938851 - 2⁹ = 2178938339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2178938351) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 81786 + ... + 105103.

It is an arithmetic number, because the mean of its divisors is an integer number (277531650).

Almost surely, 2^2178938851 is an apocalyptic number.

2178938851 is a deficient number, since it is larger than the sum of its proper divisors (41314349).

2178938851 is a wasteful number, since it uses less digits than its factorization.

2178938851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187109.

The product of its digits is 967680, while the sum is 52.

The square root of 2178938851 is about 46679.1050792536. The cubic root of 2178938851 is about 1296.4278365305.

The spelling of 2178938851 in words is "two billion, one hundred seventy-eight million, nine hundred thirty-eight thousand, eight hundred fifty-one".