1221331020123 has 8 divisors (see below), whose sum is σ = 1699243158528. Its totient is φ = 778819780904.

The previous prime is 1221331020109. The next prime is 1221331020131. The reversal of 1221331020123 is 3210201331221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221331020123 - 2⁹ = 1221331019611 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1221331020123.

It is not an unprimeable number, because it can be changed into a prime (1221331020523) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8850224715 + ... + 8850224852.

It is an arithmetic number, because the mean of its divisors is an integer number (212405394816).

Almost surely, 2^{1221331020123} is an apocalyptic number.

1221331020123 is a deficient number, since it is larger than the sum of its proper divisors (477912138405).

1221331020123 is a wasteful number, since it uses less digits than its factorization.

1221331020123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17700449593.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 1221331020123 its reverse (3210201331221), we get a palindrome (4431532351344).

The spelling of 1221331020123 in words is "one trillion, two hundred twenty-one billion, three hundred thirty-one million, twenty thousand, one hundred twenty-three".