1021200212121 has 32 divisors (see below), whose sum is σ = 1480942517760. Its totient is φ = 623316105216.

The previous prime is 1021200212117. The next prime is 1021200212171. The reversal of 1021200212121 is 1212120021201.

It is not a de Polignac number, because 1021200212121 - 2² = 1021200212117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1021200212121.

It is not an unprimeable number, because it can be changed into a prime (1021200212111) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10365325 + ... + 10463381.

It is an arithmetic number, because the mean of its divisors is an integer number (46279453680).

Almost surely, 2^{1021200212121} is an apocalyptic number.

It is an amenable number.

1021200212121 is a deficient number, since it is larger than the sum of its proper divisors (459742305639).

1021200212121 is a wasteful number, since it uses less digits than its factorization.

1021200212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103633.

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

Adding to 1021200212121 its reverse (1212120021201), we get a palindrome (2233320233322).

It can be divided in two parts, 1021200 and 212121, that added together give a palindrome (1233321).

The spelling of 1021200212121 in words is "one trillion, twenty-one billion, two hundred million, two hundred twelve thousand, one hundred twenty-one".