123121321403 has 4 divisors (see below), whose sum is σ = 127366884240. Its totient is φ = 118875758568.

The previous prime is 123121321391. The next prime is 123121321409. The reversal of 123121321403 is 304123121321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 304123121321 = 414683 ⋅733387.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123121321403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123121321409) 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, 2122781375 + ... + 2122781432.

It is an arithmetic number, because the mean of its divisors is an integer number (31841721060).

Almost surely, 2^123121321403 is an apocalyptic number.

123121321403 is a deficient number, since it is larger than the sum of its proper divisors (4245562837).

123121321403 is an equidigital number, since it uses as much as digits as its factorization.

123121321403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4245562836.

The product of its (nonzero) digits is 864, while the sum is 23.

Adding to 123121321403 its reverse (304123121321), we get a palindrome (427244442724).

The spelling of 123121321403 in words is "one hundred twenty-three billion, one hundred twenty-one million, three hundred twenty-one thousand, four hundred three".