21122221000020 has 96 divisors (see below), whose sum is σ = 67611587586816. Its totient is φ = 4826473344000.

The previous prime is 21122220999989. The next prime is 21122221000051. The reversal of 21122221000020 is 2000012222112.

It is an interprime number because it is at equal distance from previous prime (21122220999989) and next prime (21122221000051).

It is a super-2 number, since 2×21122221000020² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6231121 + ... + 9003960.

It is an arithmetic number, because the mean of its divisors is an integer number (704287370696).

Almost surely, 2^{21122221000020} is an apocalyptic number.

21122221000020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21122221000020 is an abundant number, since it is smaller than the sum of its proper divisors (46489366586796).

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

21122221000020 is a wasteful number, since it uses less digits than its factorization.

21122221000020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15238401 (or 15238399 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21122221000020 its reverse (2000012222112), we get a palindrome (23122233222132).

The spelling of 21122221000020 in words is "twenty-one trillion, one hundred twenty-two billion, two hundred twenty-one million, twenty", and thus it is an aban number.