21211210122220 has 24 divisors (see below), whose sum is σ = 45383985433584. Its totient is φ = 8324399443776.

The previous prime is 21211210122149. The next prime is 21211210122239. The reversal of 21211210122220 is 2222101211212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10005286734 + ... + 10005288853.

It is an arithmetic number, because the mean of its divisors is an integer number (1890999393066).

Almost surely, 2^{21211210122220} is an apocalyptic number.

21211210122220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211210122220 is an abundant number, since it is smaller than the sum of its proper divisors (24172775311364).

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

21211210122220 is a wasteful number, since it uses less digits than its factorization.

21211210122220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20010575649 (or 20010575647 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21211210122220 its reverse (2222101211212), we get a palindrome (23433311333432).

The spelling of 21211210122220 in words is "twenty-one trillion, two hundred eleven billion, two hundred ten million, one hundred twenty-two thousand, two hundred twenty".