1221231112010 has 128 divisors (see below), whose sum is σ = 2865266417664. Its totient is φ = 364176933120.

The previous prime is 1221231111983. The next prime is 1221231112021. The reversal of 1221231112010 is 102111321221.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221231112010.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 966875 + ... + 1837745.

It is an arithmetic number, because the mean of its divisors is an integer number (22384893888).

Almost surely, 2^{1221231112010} is an apocalyptic number.

1221231112010 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221231112010 is an abundant number, since it is smaller than the sum of its proper divisors (1644035305654).

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

1221231112010 is a wasteful number, since it uses less digits than its factorization.

1221231112010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 870988.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 1221231112010 its reverse (102111321221), we get a palindrome (1323342433231).

The spelling of 1221231112010 in words is "one trillion, two hundred twenty-one billion, two hundred thirty-one million, one hundred twelve thousand, ten".