1221131111310 has 96 divisors (see below), whose sum is σ = 3645865192320. Its totient is φ = 280451160000.

The previous prime is 1221131111309. The next prime is 1221131111311. The reversal of 1221131111310 is 131111311221.

1221131111310 is a `hidden beast` number, since 1 + 2 + 211 + 31 + 111 + 310 = 666.

It is an interprime number because it is at equal distance from previous prime (1221131111309) and next prime (1221131111311).

It is a super-2 number, since 2×1221131111310² (a number of 25 digits) contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221131111311) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 32440816 + ... + 32478435.

It is an arithmetic number, because the mean of its divisors is an integer number (37977762420).

Almost surely, 2^{1221131111310} is an apocalyptic number.

1221131111310 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221131111310 is an abundant number, since it is smaller than the sum of its proper divisors (2424734081010).

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

1221131111310 is a wasteful number, since it uses less digits than its factorization.

1221131111310 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64919294 (or 64919291 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 18.

Adding to 1221131111310 its reverse (131111311221), we get a palindrome (1352242422531).

The spelling of 1221131111310 in words is "one trillion, two hundred twenty-one billion, one hundred thirty-one million, one hundred eleven thousand, three hundred ten".