1221020023103 has 4 divisors (see below), whose sum is σ = 1221022240200. Its totient is φ = 1221017806008.

The previous prime is 1221020023073. The next prime is 1221020023109. The reversal of 1221020023103 is 3013200201221.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221020023103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221020023109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 421301 + ... + 1618497.

It is an arithmetic number, because the mean of its divisors is an integer number (305255560050).

Almost surely, 2^{1221020023103} is an apocalyptic number.

1221020023103 is a deficient number, since it is larger than the sum of its proper divisors (2217097).

1221020023103 is a wasteful number, since it uses less digits than its factorization.

1221020023103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2217096.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 1221020023103 its reverse (3013200201221), we get a palindrome (4234220224324).

The spelling of 1221020023103 in words is "one trillion, two hundred twenty-one billion, twenty million, twenty-three thousand, one hundred three".