631121 has 2 divisors, whose sum is σ = 631122. Its totient is φ = 631120.

The previous prime is 631061. The next prime is 631133. The reversal of 631121 is 121136.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 547600 + 83521 = 740^2 + 289^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-631121 is a prime.

It is equal to p₅₁₄₁₃ and since 631121 and 51413 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 631096 and 631105.

It is not a weakly prime, because it can be changed into another prime (631151) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315560 + 315561.

It is an arithmetic number, because the mean of its divisors is an integer number (315561).

2⁶³¹¹²¹ is an apocalyptic number.

It is an amenable number.

631121 is a deficient number, since it is larger than the sum of its proper divisors (1).

631121 is an equidigital number, since it uses as much as digits as its factorization.

631121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36, while the sum is 14.

The square root of 631121 is about 794.4312430916. The cubic root of 631121 is about 85.7770047573. Note that the first 3 decimals are identical.

Adding to 631121 its reverse (121136), we get a palindrome (752257).

The spelling of 631121 in words is "six hundred thirty-one thousand, one hundred twenty-one".