21211120121000 has 32 divisors (see below), whose sum is σ = 49634021085480. Its totient is φ = 8484448048000.

The previous prime is 21211120120991. The next prime is 21211120121069. The reversal of 21211120121000 is 12102111212.

It can be written as a sum of positive squares in 4 ways, for example, as 8045993210116 + 13165126910884 = 2836546^2 + 3628378^2 .

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, 10605559061 + ... + 10605561060.

Almost surely, 2^{21211120121000} is an apocalyptic number.

21211120121000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211120121000 is an abundant number, since it is smaller than the sum of its proper divisors (28422900964480).

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

21211120121000 is a wasteful number, since it uses less digits than its factorization.

21211120121000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21211120142 (or 21211120128 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21211120121000 its reverse (12102111212), we get a palindrome (21223222232212).

The spelling of 21211120121000 in words is "twenty-one trillion, two hundred eleven billion, one hundred twenty million, one hundred twenty-one thousand".