21021212012200 has 24 divisors (see below), whose sum is σ = 48874317928830. Its totient is φ = 8408484804800.

The previous prime is 21021212012123. The next prime is 21021212012201. The reversal of 21021212012200 is 221021212012.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 20436601910596 + 584610101604 = 4520686^2 + 764598^2 .

It is not an unprimeable number, because it can be changed into a prime (21021212012201) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 52553029831 + ... + 52553030230.

Almost surely, 2^{21021212012200} is an apocalyptic number.

21021212012200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21021212012200 is an abundant number, since it is smaller than the sum of its proper divisors (27853105916630).

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

21021212012200 is a wasteful number, since it uses less digits than its factorization.

21021212012200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105106060077 (or 105106060068 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21021212012200 its reverse (221021212012), we get a palindrome (21242233224212).

The spelling of 21021212012200 in words is "twenty-one trillion, twenty-one billion, two hundred twelve million, twelve thousand, two hundred".