123331231021 has 4 divisors (see below), whose sum is σ = 123345196092. Its totient is φ = 123317265952.

The previous prime is 123331231019. The next prime is 123331231043. The reversal of 123331231021 is 120132133321.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 77847138121 + 45484092900 = 279011^2 + 213270^2 .

It is a cyclic number.

It is not a de Polignac number, because 123331231021 - 2¹ = 123331231019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 123331230983 and 123331231001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123331231061) 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, 6969280 + ... + 6986953.

It is an arithmetic number, because the mean of its divisors is an integer number (30836299023).

Almost surely, 2^123331231021 is an apocalyptic number.

It is an amenable number.

123331231021 is a deficient number, since it is larger than the sum of its proper divisors (13965071).

123331231021 is an equidigital number, since it uses as much as digits as its factorization.

123331231021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13965070.

The product of its (nonzero) digits is 648, while the sum is 22.

Adding to 123331231021 its reverse (120132133321), we get a palindrome (243463364342).

It can be divided in two parts, 12333123 and 1021, that added together give a square (12334144 = 3512²).

The spelling of 123331231021 in words is "one hundred twenty-three billion, three hundred thirty-one million, two hundred thirty-one thousand, twenty-one".