21122122121220 has 48 divisors (see below), whose sum is σ = 59142165058368. Its totient is φ = 5632544649600.

The previous prime is 21122122121203. The next prime is 21122122121257. The reversal of 21122122121220 is 2212122122112.

It is a super-2 number, since 2×21122122121220² (a number of 27 digits) contains 22 as substring.

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, 21469942 + ... + 22432178.

It is an arithmetic number, because the mean of its divisors is an integer number (1232128438716).

Almost surely, 2^{21122122121220} is an apocalyptic number.

21122122121220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21122122121220 is an abundant number, since it is smaller than the sum of its proper divisors (38020042937148).

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

21122122121220 is a wasteful number, since it uses less digits than its factorization.

21122122121220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1328100 (or 1328098 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 21122122121220 its reverse (2212122122112), we get a palindrome (23334244243332).

The spelling of 21122122121220 in words is "twenty-one trillion, one hundred twenty-two billion, one hundred twenty-two million, one hundred twenty-one thousand, two hundred twenty".