21005332000 has 48 divisors (see below), whose sum is σ = 51610110552. Its totient is φ = 8402131200.

The previous prime is 21005331989. The next prime is 21005332013. The reversal of 21005332000 is 23350012.

It can be written as a sum of positive squares in 4 ways, for example, as 10901865744 + 10103466256 = 104412^2 + 100516^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2621667 + ... + 2629666.

Almost surely, 2^21005332000 is an apocalyptic number.

21005332000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21005332000 is an abundant number, since it is smaller than the sum of its proper divisors (30604778552).

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

21005332000 is an equidigital number, since it uses as much as digits as its factorization.

21005332000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5251358 (or 5251340 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 16.

Adding to 21005332000 its reverse (23350012), we get a palindrome (21028682012).

The spelling of 21005332000 in words is "twenty-one billion, five million, three hundred thirty-two thousand".