1221338530 has 16 divisors (see below), whose sum is σ = 2206968120. Its totient is φ = 486633472.

The previous prime is 1221338477. The next prime is 1221338549. The reversal of 1221338530 is 358331221.

It can be written as a sum of positive squares in 4 ways, for example, as 1215428769 + 5909761 = 34863^2 + 2431^2 .

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, 235045 + ... + 240184.

Almost surely, 2^1221338530 is an apocalyptic number.

1221338530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221338530 is a deficient number, since it is larger than the sum of its proper divisors (985629590).

1221338530 is a wasteful number, since it uses less digits than its factorization.

1221338530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 475493.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 1221338530 is about 34947.6541415872. The cubic root of 1221338530 is about 1068.9203684948.

Adding to 1221338530 its reverse (358331221), we get a palindrome (1579669751).

The spelling of 1221338530 in words is "one billion, two hundred twenty-one million, three hundred thirty-eight thousand, five hundred thirty".