21821071188 has 48 divisors (see below), whose sum is σ = 58203339264. Its totient is φ = 6233111520.

The previous prime is 21821071177. The next prime is 21821071241. The reversal of 21821071188 is 88117012812.

It is a congruent number.

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, 353383 + ... + 410513.

It is an arithmetic number, because the mean of its divisors is an integer number (1212569568).

Almost surely, 2^21821071188 is an apocalyptic number.

21821071188 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21821071188 is an abundant number, since it is smaller than the sum of its proper divisors (36382268076).

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

21821071188 is a wasteful number, since it uses less digits than its factorization.

21821071188 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61692 (or 61690 counting only the distinct ones).

The product of its (nonzero) digits is 14336, while the sum is 39.

The spelling of 21821071188 in words is "twenty-one billion, eight hundred twenty-one million, seventy-one thousand, one hundred eighty-eight".