631631401 has 2 divisors, whose sum is σ = 631631402. Its totient is φ = 631631400.

The previous prime is 631631387. The next prime is 631631419. The reversal of 631631401 is 104136136.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 631215376 + 416025 = 25124^2 + 645^2 .

It is a cyclic number.

It is not a de Polignac number, because 631631401 - 2¹¹ = 631629353 is a prime.

It is not a weakly prime, because it can be changed into another prime (631631431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315815700 + 315815701.

It is an arithmetic number, because the mean of its divisors is an integer number (315815701).

Almost surely, 2^631631401 is an apocalyptic number.

It is an amenable number.

631631401 is a deficient number, since it is larger than the sum of its proper divisors (1).

631631401 is an equidigital number, since it uses as much as digits as its factorization.

631631401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 631631401 is about 25132.2780702427. The cubic root of 631631401 is about 858.0012175712.

Adding to 631631401 its reverse (104136136), we get a palindrome (735767537).

The spelling of 631631401 in words is "six hundred thirty-one million, six hundred thirty-one thousand, four hundred one".