1221020140044 has 12 divisors (see below), whose sum is σ = 2849046993464. Its totient is φ = 407006713344.

The previous prime is 1221020140037. The next prime is 1221020140147. The reversal of 1221020140044 is 4400410201221.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 1221020140044.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50875839157 + ... + 50875839180.

Almost surely, 2^{1221020140044} is an apocalyptic number.

It is an amenable number.

1221020140044 is an abundant number, since it is smaller than the sum of its proper divisors (1628026853420).

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

1221020140044 is a wasteful number, since it uses less digits than its factorization.

1221020140044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101751678344 (or 101751678342 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 21.

Adding to 1221020140044 its reverse (4400410201221), we get a palindrome (5621430341265).

The spelling of 1221020140044 in words is "one trillion, two hundred twenty-one billion, twenty million, one hundred forty thousand, forty-four".