123212300021 has 4 divisors (see below), whose sum is σ = 123295496844. Its totient is φ = 123129103200.

The previous prime is 123212299999. The next prime is 123212300033. The reversal of 123212300021 is 120003212321.

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 74188140625 + 49024159396 = 272375^2 + 221414^2 .

It is a cyclic number.

It is not a de Polignac number, because 123212300021 - 2³⁴ = 106032430837 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 (123212300821) 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, 41596190 + ... + 41599151.

It is an arithmetic number, because the mean of its divisors is an integer number (30823874211).

Almost surely, 2^123212300021 is an apocalyptic number.

It is an amenable number.

123212300021 is a deficient number, since it is larger than the sum of its proper divisors (83196823).

123212300021 is an equidigital number, since it uses as much as digits as its factorization.

123212300021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83196822.

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

Adding to 123212300021 its reverse (120003212321), we get a palindrome (243215512342).

The spelling of 123212300021 in words is "one hundred twenty-three billion, two hundred twelve million, three hundred thousand, twenty-one".