21000021021324 has 36 divisors (see below), whose sum is σ = 53875675827064. Its totient is φ = 6895529289792.

The previous prime is 21000021021323. The next prime is 21000021021341. The reversal of 21000021021324 is 42312012000012.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21000021021297 and 21000021021306.

It is not an unprimeable number, because it can be changed into a prime (21000021021323) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4353235777 + ... + 4353240600.

Almost surely, 2^{21000021021324} is an apocalyptic number.

It is an amenable number.

21000021021324 is an abundant number, since it is smaller than the sum of its proper divisors (32875654805740).

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

21000021021324 is a wasteful number, since it uses less digits than its factorization.

21000021021324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8706476454 (or 8706476449 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21000021021324 its reverse (42312012000012), we get a palindrome (63312033021336).

The spelling of 21000021021324 in words is "twenty-one trillion, twenty-one million, twenty-one thousand, three hundred twenty-four".