1213332120021 has 16 divisors (see below), whose sum is σ = 1891884414464. Its totient is φ = 677208624624.

The previous prime is 1213332120001. The next prime is 1213332120043. The reversal of 1213332120021 is 1200212333121.

It is not a de Polignac number, because 1213332120021 - 2³³ = 1204742185429 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1213332120021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213332120001) 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, 671833051 + ... + 671834856.

It is an arithmetic number, because the mean of its divisors is an integer number (118242775904).

Almost surely, 2^{1213332120021} is an apocalyptic number.

It is an amenable number.

1213332120021 is a deficient number, since it is larger than the sum of its proper divisors (678552294443).

1213332120021 is a wasteful number, since it uses less digits than its factorization.

1213332120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1343667960.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 1213332120021 its reverse (1200212333121), we get a palindrome (2413544453142).

The spelling of 1213332120021 in words is "one trillion, two hundred thirteen billion, three hundred thirty-two million, one hundred twenty thousand, twenty-one".