1221022001142 has 24 divisors (see below), whose sum is σ = 2679035617440. Its totient is φ = 401855341680.

The previous prime is 1221022001141. The next prime is 1221022001153. The reversal of 1221022001142 is 2411002201221.

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 (1221022001141) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 429331209 + ... + 429334052.

It is an arithmetic number, because the mean of its divisors is an integer number (111626484060).

Almost surely, 2^{1221022001142} is an apocalyptic number.

1221022001142 is an abundant number, since it is smaller than the sum of its proper divisors (1458013616298).

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

1221022001142 is a wasteful number, since it uses less digits than its factorization.

1221022001142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 858665348 (or 858665345 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 1221022001142 its reverse (2411002201221), we get a palindrome (3632024202363).

The spelling of 1221022001142 in words is "one trillion, two hundred twenty-one billion, twenty-two million, one thousand, one hundred forty-two".