21121022002100 has 36 divisors (see below), whose sum is σ = 46950486479148. Its totient is φ = 8242350048000.

The previous prime is 21121022002079. The next prime is 21121022002117. The reversal of 21121022002100 is 120022012112.

It can be written as a sum of positive squares in 6 ways, for example, as 369462171556 + 20751559830544 = 607834^2 + 4555388^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2575730291 + ... + 2575738490.

Almost surely, 2^{21121022002100} is an apocalyptic number.

21121022002100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121022002100 is an abundant number, since it is smaller than the sum of its proper divisors (25829464477048).

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

21121022002100 is a wasteful number, since it uses less digits than its factorization.

21121022002100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5151468836 (or 5151468829 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21121022002100 its reverse (120022012112), we get a palindrome (21241044014212).

The spelling of 21121022002100 in words is "twenty-one trillion, one hundred twenty-one billion, twenty-two million, two thousand, one hundred".