21071128832 has 36 divisors (see below), whose sum is σ = 45295336380. Its totient is φ = 9725134848.

The previous prime is 21071128831. The next prime is 21071128847. The reversal of 21071128832 is 23882117012.

It can be written as a sum of positive squares in 2 ways, for example, as 8016695296 + 13054433536 = 89536^2 + 114256^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21071128792 and 21071128801.

It is not an unprimeable number, because it can be changed into a prime (21071128831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3162407 + ... + 3169062.

Almost surely, 2^21071128832 is an apocalyptic number.

It is an amenable number.

21071128832 is an abundant number, since it is smaller than the sum of its proper divisors (24224207548).

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

21071128832 is an equidigital number, since it uses as much as digits as its factorization.

21071128832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6331498 (or 6331484 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 35.

The spelling of 21071128832 in words is "twenty-one billion, seventy-one million, one hundred twenty-eight thousand, eight hundred thirty-two".