1321000123 has 4 divisors (see below), whose sum is σ = 1321257888. Its totient is φ = 1320742360.

The previous prime is 1321000081. The next prime is 1321000127. The reversal of 1321000123 is 3210001231.

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

It is a cyclic number.

It is not a de Polignac number, because 1321000123 - 2²¹ = 1318902971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1321000127) 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, 121036 + ... + 131497.

It is an arithmetic number, because the mean of its divisors is an integer number (330314472).

Almost surely, 2^1321000123 is an apocalyptic number.

1321000123 is a deficient number, since it is larger than the sum of its proper divisors (257765).

1321000123 is an equidigital number, since it uses as much as digits as its factorization.

1321000123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257764.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 1321000123 is about 36345.5653828634. The cubic root of 1321000123 is about 1097.2382850508.

Adding to 1321000123 its reverse (3210001231), we get a palindrome (4531001354).

The spelling of 1321000123 in words is "one billion, three hundred twenty-one million, one hundred twenty-three", and thus it is an aban number.