2179431681 has 8 divisors (see below), whose sum is σ = 3321038784. Its totient is φ = 1245389520.

The previous prime is 2179431643. The next prime is 2179431707. The reversal of 2179431681 is 1861349712.

It is a happy number.

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

It is not a de Polignac number, because 2179431681 - 2¹⁰ = 2179430657 is a prime.

It is a super-2 number, since 2×2179431681² = 9499844904292971522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (2179431641) 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, 51891210 + ... + 51891251.

It is an arithmetic number, because the mean of its divisors is an integer number (415129848).

Almost surely, 2^2179431681 is an apocalyptic number.

2179431681 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2179431681 is a deficient number, since it is larger than the sum of its proper divisors (1141607103).

2179431681 is a wasteful number, since it uses less digits than its factorization.

2179431681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103782471.

The product of its digits is 72576, while the sum is 42.

The square root of 2179431681 is about 46684.3836951930. The cubic root of 2179431681 is about 1296.5255707046.

The spelling of 2179431681 in words is "two billion, one hundred seventy-nine million, four hundred thirty-one thousand, six hundred eighty-one".