211631401 has 2 divisors, whose sum is σ = 211631402. Its totient is φ = 211631400.

The previous prime is 211631377. The next prime is 211631411. The reversal of 211631401 is 104136112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 199374400 + 12257001 = 14120^2 + 3501^2 .

It is a cyclic number.

It is not a de Polignac number, because 211631401 - 2²¹ = 209534249 is a prime.

It is not a weakly prime, because it can be changed into another prime (211631411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105815700 + 105815701.

It is an arithmetic number, because the mean of its divisors is an integer number (105815701).

Almost surely, 2^211631401 is an apocalyptic number.

It is an amenable number.

211631401 is a deficient number, since it is larger than the sum of its proper divisors (1).

211631401 is an equidigital number, since it uses as much as digits as its factorization.

211631401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 211631401 is about 14547.5565302218. The cubic root of 211631401 is about 595.9274202941.

Adding to 211631401 its reverse (104136112), we get a palindrome (315767513).

The spelling of 211631401 in words is "two hundred eleven million, six hundred thirty-one thousand, four hundred one".