1221353340 has 24 divisors (see below), whose sum is σ = 3419789520. Its totient is φ = 325694208.

The previous prime is 1221353317. The next prime is 1221353401. The reversal of 1221353340 is 433531221.

It is a super-2 number, since 2×1221353340² = 2983407962258311200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1221353340.

It is a congruent number.

It is an unprimeable number.

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, 10177885 + ... + 10178004.

It is an arithmetic number, because the mean of its divisors is an integer number (142491230).

Almost surely, 2^1221353340 is an apocalyptic number.

1221353340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221353340 is an abundant number, since it is smaller than the sum of its proper divisors (2198436180).

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

1221353340 is a wasteful number, since it uses less digits than its factorization.

1221353340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20355901 (or 20355899 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 1221353340 is about 34947.8660292728. The cubic root of 1221353340 is about 1068.9246890677.

Adding to 1221353340 its reverse (433531221), we get a palindrome (1654884561).

The spelling of 1221353340 in words is "one billion, two hundred twenty-one million, three hundred fifty-three thousand, three hundred forty".