1221203400213 has 16 divisors (see below), whose sum is σ = 1635048721152. Its totient is φ = 810753600000.

The previous prime is 1221203400203. The next prime is 1221203400251. The reversal of 1221203400213 is 3120043021221.

It is not a de Polignac number, because 1221203400213 - 2⁸ = 1221203399957 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1221203400213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221203400203) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 121533 + ... + 1567538.

It is an arithmetic number, because the mean of its divisors is an integer number (102190545072).

Almost surely, 2^{1221203400213} is an apocalyptic number.

It is an amenable number.

1221203400213 is a deficient number, since it is larger than the sum of its proper divisors (413845320939).

1221203400213 is a wasteful number, since it uses less digits than its factorization.

1221203400213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1690076.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 1221203400213 its reverse (3120043021221), we get a palindrome (4341246421434).

The spelling of 1221203400213 in words is "one trillion, two hundred twenty-one billion, two hundred three million, four hundred thousand, two hundred thirteen".