321323921 has 2 divisors, whose sum is σ = 321323922. Its totient is φ = 321323920.

The previous prime is 321323917. The next prime is 321323927. The reversal of 321323921 is 129323123.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 247621696 + 73702225 = 15736^2 + 8585^2 .

It is an emirp because it is prime and its reverse (129323123) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 321323921 - 2² = 321323917 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (321323927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160661960 + 160661961.

It is an arithmetic number, because the mean of its divisors is an integer number (160661961).

Almost surely, 2^321323921 is an apocalyptic number.

It is an amenable number.

321323921 is a deficient number, since it is larger than the sum of its proper divisors (1).

321323921 is an equidigital number, since it uses as much as digits as its factorization.

321323921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1944, while the sum is 26.

The square root of 321323921 is about 17925.5103414101. The cubic root of 321323921 is about 684.9323612330.

The spelling of 321323921 in words is "three hundred twenty-one million, three hundred twenty-three thousand, nine hundred twenty-one".