21000335240000 has 140 divisors (see below), whose sum is σ = 52091828503968. Its totient is φ = 8397259200000.

The previous prime is 21000335239993. The next prime is 21000335240039. The reversal of 21000335240000 is 4253300012.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 118751645 + ... + 118928355.

Almost surely, 2^{21000335240000} is an apocalyptic number.

21000335240000 is a gapful number since it is divisible by the number (20) 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 21000335240000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26045914251984).

21000335240000 is an abundant number, since it is smaller than the sum of its proper divisors (31091493263968).

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

21000335240000 is an equidigital number, since it uses as much as digits as its factorization.

21000335240000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179714 (or 179689 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

Adding to 21000335240000 its reverse (4253300012), we get a palindrome (21004588540012).

The spelling of 21000335240000 in words is "twenty-one trillion, three hundred thirty-five million, two hundred forty thousand".