1221313002 has 128 divisors (see below), whose sum is σ = 3119316480. Its totient is φ = 310210560.

The previous prime is 1221312977. The next prime is 1221313007. The reversal of 1221313002 is 2003131221.

It is not an unprimeable number, because it can be changed into a prime (1221313007) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1992048 + ... + 1992660.

It is an arithmetic number, because the mean of its divisors is an integer number (24369660).

Almost surely, 2^1221313002 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221313002, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1559658240).

1221313002 is an abundant number, since it is smaller than the sum of its proper divisors (1898003478).

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

1221313002 is a wasteful number, since it uses less digits than its factorization.

1221313002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 768.

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 1221313002 is about 34947.2889077250. The cubic root of 1221313002 is about 1068.9129210403.

Adding to 1221313002 its reverse (2003131221), we get a palindrome (3224444223).

The spelling of 1221313002 in words is "one billion, two hundred twenty-one million, three hundred thirteen thousand, two".