2178661944 has 32 divisors (see below), whose sum is σ = 5457600000. Its totient is φ = 724761312.

The previous prime is 2178661939. The next prime is 2178661967. The reversal of 2178661944 is 4491668712.

It is a junction number, because it is equal to n+sod(n) for n = 2178661893 and 2178661902.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78984 + ... + 102935.

It is an arithmetic number, because the mean of its divisors is an integer number (170550000).

Almost surely, 2^2178661944 is an apocalyptic number.

2178661944 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

2178661944 is an abundant number, since it is smaller than the sum of its proper divisors (3278938056).

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

2178661944 is a wasteful number, since it uses less digits than its factorization.

2178661944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182427 (or 182423 counting only the distinct ones).

The product of its digits is 580608, while the sum is 48.

The square root of 2178661944 is about 46676.1389148674. The cubic root of 2178661944 is about 1296.3729160431.

The spelling of 2178661944 in words is "two billion, one hundred seventy-eight million, six hundred sixty-one thousand, nine hundred forty-four".