1221513102 has 16 divisors (see below), whose sum is σ = 2714473680. Its totient is φ = 407171016.

The previous prime is 1221513043. The next prime is 1221513103. The reversal of 1221513102 is 2013151221.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221513103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11310253 + ... + 11310360.

It is an arithmetic number, because the mean of its divisors is an integer number (169654605).

Almost surely, 2^1221513102 is an apocalyptic number.

1221513102 is an abundant number, since it is smaller than the sum of its proper divisors (1492960578).

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

1221513102 is a wasteful number, since it uses less digits than its factorization.

1221513102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22620624 (or 22620618 counting only the distinct ones).

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

The square root of 1221513102 is about 34950.1516734906. The cubic root of 1221513102 is about 1068.9712947728.

Adding to 1221513102 its reverse (2013151221), we get a palindrome (3234664323).

The spelling of 1221513102 in words is "one billion, two hundred twenty-one million, five hundred thirteen thousand, one hundred two".