1221121210200 has 48 divisors (see below), whose sum is σ = 3785475753480. Its totient is φ = 325632322560.

The previous prime is 1221121210189. The next prime is 1221121210217. The reversal of 1221121210200 is 20121211221.

It is a super-2 number, since 2×1221121210200² (a number of 25 digits) contains 22 as substring.

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 1221121210200.

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, 1017600409 + ... + 1017601608.

Almost surely, 2^{1221121210200} is an apocalyptic number.

1221121210200 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221121210200 is an abundant number, since it is smaller than the sum of its proper divisors (2564354543280).

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

1221121210200 is a wasteful number, since it uses less digits than its factorization.

1221121210200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2035202036 (or 2035202027 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 1221121210200 its reverse (20121211221), we get a palindrome (1241242421421).

The spelling of 1221121210200 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred ten thousand, two hundred".