315421 has 2 divisors, whose sum is σ = 315422. Its totient is φ = 315420.

The previous prime is 315409. The next prime is 315437. The reversal of 315421 is 124513.

It is an a-pointer prime, because the next prime (315437) can be obtained adding 315421 to its sum of digits (16).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 308025 + 7396 = 555^2 + 86^2 .

It is an emirp because it is prime and its reverse (124513) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 315421 - 2⁵ = 315389 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 315395 and 315404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (315451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 157710 + 157711.

It is an arithmetic number, because the mean of its divisors is an integer number (157711).

2³¹⁵⁴²¹ is an apocalyptic number.

It is an amenable number.

315421 is a deficient number, since it is larger than the sum of its proper divisors (1).

315421 is an equidigital number, since it uses as much as digits as its factorization.

315421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120, while the sum is 16.

The square root of 315421 is about 561.6235393927. The cubic root of 315421 is about 68.0712200757.

Adding to 315421 its reverse (124513), we get a palindrome (439934).

The spelling of 315421 in words is "three hundred fifteen thousand, four hundred twenty-one".