1221300120 has 64 divisors (see below), whose sum is σ = 3718609920. Its totient is φ = 320817024.

The previous prime is 1221300109. The next prime is 1221300127. The reversal of 1221300120 is 210031221.

It is a super-2 number, since 2×1221300120² = 2983147966224028800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 1221300096 and 1221300105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221300127) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67912 + ... + 83991.

It is an arithmetic number, because the mean of its divisors is an integer number (58103280).

Almost surely, 2^1221300120 is an apocalyptic number.

1221300120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221300120 is an abundant number, since it is smaller than the sum of its proper divisors (2497309800).

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

1221300120 is a wasteful number, since it uses less digits than its factorization.

1221300120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151984 (or 151980 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 1221300120 is about 34947.1046010968. The cubic root of 1221300120 is about 1068.9091628487.

Adding to 1221300120 its reverse (210031221), we get a palindrome (1431331341).

The spelling of 1221300120 in words is "one billion, two hundred twenty-one million, three hundred thousand, one hundred twenty".