1221360631221 has 16 divisors (see below), whose sum is σ = 1724703793344. Its totient is φ = 766152831744.

The previous prime is 1221360631201. The next prime is 1221360631237.

1221360631221 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1221360631221 - 2¹⁰ = 1221360630197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221360631201) 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, 2779171 + ... + 3188496.

It is an arithmetic number, because the mean of its divisors is an integer number (107793987084).

Almost surely, 2^{1221360631221} is an apocalyptic number.

It is an amenable number.

1221360631221 is a deficient number, since it is larger than the sum of its proper divisors (503343162123).

1221360631221 is a wasteful number, since it uses less digits than its factorization.

1221360631221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5971700.

The product of its (nonzero) digits is 5184, while the sum is 30.

It can be divided in two parts, 1221360 and 631221, that added together give a palindrome (1852581).

The spelling of 1221360631221 in words is "one trillion, two hundred twenty-one billion, three hundred sixty million, six hundred thirty-one thousand, two hundred twenty-one".