321126401 has 4 divisors (see below), whose sum is σ = 321228372. Its totient is φ = 321024432.

The previous prime is 321126373. The next prime is 321126431. The reversal of 321126401 is 104621123.

It is a Cunningham number, because it is equal to 17920²+1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 104621123 = 5483 ⋅19081.

It can be written as a sum of positive squares in 2 ways, for example, as 319551376 + 1575025 = 17876^2 + 1255^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-321126401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (321126431) 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, 46106 + ... + 52611.

It is an arithmetic number, because the mean of its divisors is an integer number (80307093).

It is a Proth number, since it is equal to 1225 ⋅ 2¹⁸ + 1 and 1225 < 2¹⁸.

Almost surely, 2^321126401 is an apocalyptic number.

It is an amenable number.

321126401 is a deficient number, since it is larger than the sum of its proper divisors (101971).

321126401 is an equidigital number, since it uses as much as digits as its factorization.

321126401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101970.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 321126401 is about 17920.0000279018. Note that the first 4 decimals coincide. The cubic root of 321126401 is about 684.7919882725.

Adding to 321126401 its reverse (104621123), we get a palindrome (425747524).

The spelling of 321126401 in words is "three hundred twenty-one million, one hundred twenty-six thousand, four hundred one".