1221302120 has 32 divisors (see below), whose sum is σ = 2759744520. Its totient is φ = 486420480.

The previous prime is 1221302119. The next prime is 1221302149. The reversal of 1221302120 is 212031221.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 407797636 + 813504484 = 20194^2 + 28522^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1221302095 and 1221302104.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56201 + ... + 74840.

Almost surely, 2^1221302120 is an apocalyptic number.

1221302120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221302120 is an abundant number, since it is smaller than the sum of its proper divisors (1538442400).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221302120 is a wasteful number, since it uses less digits than its factorization.

1221302120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131285 (or 131281 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 1221302120 is about 34947.1332157589. The cubic root of 1221302120 is about 1068.9097463300.

Adding to 1221302120 its reverse (212031221), we get a palindrome (1433333341).

The spelling of 1221302120 in words is "one billion, two hundred twenty-one million, three hundred two thousand, one hundred twenty".