21221134134020 has 48 divisors (see below), whose sum is σ = 45304810441968. Its totient is φ = 8347480220160.

The previous prime is 21221134134017. The next prime is 21221134134049. The reversal of 21221134134020 is 2043143112212.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 8251095390784 + 12970038743236 = 2872472^2 + 3601394^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3716414 + ... + 7500266.

It is an arithmetic number, because the mean of its divisors is an integer number (943850217541).

Almost surely, 2^{21221134134020} is an apocalyptic number.

21221134134020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221134134020 is an abundant number, since it is smaller than the sum of its proper divisors (24083676307948).

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

21221134134020 is a wasteful number, since it uses less digits than its factorization.

21221134134020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3788520 (or 3788518 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

Adding to 21221134134020 its reverse (2043143112212), we get a palindrome (23264277246232).

The spelling of 21221134134020 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred thirty-four million, one hundred thirty-four thousand, twenty".