1221301215 has 48 divisors (see below), whose sum is σ = 2207462400. Its totient is φ = 623863296.

The previous prime is 1221301163. The next prime is 1221301223. The reversal of 1221301215 is 5121031221.

It is not a de Polignac number, because 1221301215 - 2¹⁰ = 1221300191 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 162051 + ... + 169419.

It is an arithmetic number, because the mean of its divisors is an integer number (45988800).

Almost surely, 2^1221301215 is an apocalyptic number.

1221301215 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1221301215 is a deficient number, since it is larger than the sum of its proper divisors (986161185).

1221301215 is a wasteful number, since it uses less digits than its factorization.

1221301215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7536 (or 7533 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 1221301215 is about 34947.1202676272. The cubic root of 1221301215 is about 1068.9094823048.

Adding to 1221301215 its reverse (5121031221), we get a palindrome (6342332436).

The spelling of 1221301215 in words is "one billion, two hundred twenty-one million, three hundred one thousand, two hundred fifteen".