21001021222200 has 48 divisors (see below), whose sum is σ = 65103165790680. Its totient is φ = 5600272325760.

The previous prime is 21001021222183. The next prime is 21001021222249. The reversal of 21001021222200 is 222212010012.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21001021222200.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17500850419 + ... + 17500851618.

Almost surely, 2^{21001021222200} is an apocalyptic number.

21001021222200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001021222200 is an abundant number, since it is smaller than the sum of its proper divisors (44102144568480).

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

21001021222200 is a wasteful number, since it uses less digits than its factorization.

21001021222200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35001702056 (or 35001702047 counting only the distinct ones).

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

Adding to 21001021222200 its reverse (222212010012), we get a palindrome (21223233232212).

The spelling of 21001021222200 in words is "twenty-one trillion, one billion, twenty-one million, two hundred twenty-two thousand, two hundred".