21022827012 has 108 divisors (see below), whose sum is σ = 58588638108. Its totient is φ = 6351206400.

The previous prime is 21022826999. The next prime is 21022827043. The reversal of 21022827012 is 21072822012.

It can be written as a sum of positive squares in 2 ways, for example, as 2158903296 + 18863923716 = 46464^2 + 137346^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1460812 + ... + 1475132.

Almost surely, 2^21022827012 is an apocalyptic number.

21022827012 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21022827012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29294319054).

21022827012 is an abundant number, since it is smaller than the sum of its proper divisors (37565811096).

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

21022827012 is a wasteful number, since it uses less digits than its factorization.

21022827012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14690 (or 14674 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

Subtracting 21022827012 from its reverse (21072822012), we obtain a triangular number (49995000 = T₉₉₉₉).

The spelling of 21022827012 in words is "twenty-one billion, twenty-two million, eight hundred twenty-seven thousand, twelve".