21002131311320 has 64 divisors (see below), whose sum is σ = 47393397324000. Its totient is φ = 8376215454720.

The previous prime is 21002131311269. The next prime is 21002131311323. The reversal of 21002131311320 is 2311313120012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 21002131311292 and 21002131311301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002131311323) 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, 251056700 + ... + 251140340.

Almost surely, 2^{21002131311320} is an apocalyptic number.

21002131311320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002131311320 is an abundant number, since it is smaller than the sum of its proper divisors (26391266012680).

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

21002131311320 is a wasteful number, since it uses less digits than its factorization.

21002131311320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101988 (or 101984 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

Adding to 21002131311320 its reverse (2311313120012), we get a palindrome (23313444431332).

The spelling of 21002131311320 in words is "twenty-one trillion, two billion, one hundred thirty-one million, three hundred eleven thousand, three hundred twenty".