21831047178 has 32 divisors (see below), whose sum is σ = 44037069120. Its totient is φ = 7214787840.

The previous prime is 21831047129. The next prime is 21831047207. The reversal of 21831047178 is 87174013812.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 294988 + ... + 361496.

It is an arithmetic number, because the mean of its divisors is an integer number (1376158410).

Almost surely, 2^21831047178 is an apocalyptic number.

21831047178 is an abundant number, since it is smaller than the sum of its proper divisors (22206021942).

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

21831047178 is a wasteful number, since it uses less digits than its factorization.

21831047178 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66982.

The product of its (nonzero) digits is 75264, while the sum is 42.

The spelling of 21831047178 in words is "twenty-one billion, eight hundred thirty-one million, forty-seven thousand, one hundred seventy-eight".