1361211437221 has 4 divisors (see below), whose sum is σ = 1441282698252. Its totient is φ = 1281140176192.

The previous prime is 1361211437203. The next prime is 1361211437249. The reversal of 1361211437221 is 1227341121631.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 862457686596 + 498753750625 = 928686^2 + 706225^2 .

It is a cyclic number.

It is not a de Polignac number, because 1361211437221 - 2¹¹ = 1361211435173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1361211417221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40035630490 + ... + 40035630523.

It is an arithmetic number, because the mean of its divisors is an integer number (360320674563).

Almost surely, 2^{1361211437221} is an apocalyptic number.

It is an amenable number.

1361211437221 is a deficient number, since it is larger than the sum of its proper divisors (80071261031).

1361211437221 is an equidigital number, since it uses as much as digits as its factorization.

1361211437221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80071261030.

The product of its digits is 12096, while the sum is 34.

Adding to 1361211437221 its reverse (1227341121631), we get a palindrome (2588552558852).

The spelling of 1361211437221 in words is "one trillion, three hundred sixty-one billion, two hundred eleven million, four hundred thirty-seven thousand, two hundred twenty-one".