21021532142320 has 80 divisors (see below), whose sum is σ = 50197203735840. Its totient is φ = 8181158464512.

The previous prime is 21021532142291. The next prime is 21021532142321. The reversal of 21021532142320 is 2324123512012.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×21021532142320² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021532142321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 233478271 + ... + 233568289.

It is an arithmetic number, because the mean of its divisors is an integer number (627465046698).

Almost surely, 2^{21021532142320} is an apocalyptic number.

21021532142320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21021532142320 is an abundant number, since it is smaller than the sum of its proper divisors (29175671593520).

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

21021532142320 is a wasteful number, since it uses less digits than its factorization.

21021532142320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168962 (or 168956 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

Adding to 21021532142320 its reverse (2324123512012), we get a palindrome (23345655654332).

The spelling of 21021532142320 in words is "twenty-one trillion, twenty-one billion, five hundred thirty-two million, one hundred forty-two thousand, three hundred twenty".