1221231330 has 160 divisors (see below), whose sum is σ = 3670748928. Its totient is φ = 288748800.

The previous prime is 1221231317. The next prime is 1221231331. The reversal of 1221231330 is 331321221.

It is a super-2 number, since 2×1221231330² = 2982811922747137800, which contains 22 as substring.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1221231331) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 363639 + ... + 366981.

Almost surely, 2^1221231330 is an apocalyptic number.

1221231330 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221231330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1835374464).

1221231330 is an abundant number, since it is smaller than the sum of its proper divisors (2449517598).

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

1221231330 is a wasteful number, since it uses less digits than its factorization.

1221231330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3414 (or 3405 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 1221231330 is about 34946.1203855306. The cubic root of 1221231330 is about 1068.8890936234.

Adding to 1221231330 its reverse (331321221), we get a palindrome (1552552551).

The spelling of 1221231330 in words is "one billion, two hundred twenty-one million, two hundred thirty-one thousand, three hundred thirty".