1221301311000 has 128 divisors (see below), whose sum is σ = 3976132492800. Its totient is φ = 311520316800.

The previous prime is 1221301310993. The next prime is 1221301311007. The reversal of 1221301311000 is 1131031221.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1221301310993) and next prime (1221301311007).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221301311007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8781010 + ... + 8919009.

It is an arithmetic number, because the mean of its divisors is an integer number (31063535100).

Almost surely, 2^{1221301311000} is an apocalyptic number.

1221301311000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221301311000 is an abundant number, since it is smaller than the sum of its proper divisors (2754831181800).

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

1221301311000 is a wasteful number, since it uses less digits than its factorization.

1221301311000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17700066 (or 17700052 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 1221301311000 its reverse (1131031221), we get a palindrome (1222432342221).

The spelling of 1221301311000 in words is "one trillion, two hundred twenty-one billion, three hundred one million, three hundred eleven thousand".