21122210020 has 12 divisors (see below), whose sum is σ = 44356641084. Its totient is φ = 8448884000.

The previous prime is 21122209993. The next prime is 21122210027. The reversal of 21122210020 is 2001222112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 12624320164 + 8497889856 = 112358^2 + 92184^2 .

It is a super-2 number, since 2×21122210020² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21122210027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 528055231 + ... + 528055270.

It is an arithmetic number, because the mean of its divisors is an integer number (3696386757).

Almost surely, 2^21122210020 is an apocalyptic number.

21122210020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21122210020 is an abundant number, since it is smaller than the sum of its proper divisors (23234431064).

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

21122210020 is a wasteful number, since it uses less digits than its factorization.

21122210020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1056110510 (or 1056110508 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21122210020 its reverse (2001222112), we get a palindrome (23123432132).

The spelling of 21122210020 in words is "twenty-one billion, one hundred twenty-two million, two hundred ten thousand, twenty".