1209631 has 2 divisors, whose sum is σ = 1209632. Its totient is φ = 1209630.

The previous prime is 1209629. The next prime is 1209647. The reversal of 1209631 is 1369021.

It is a weak prime.

It is an emirp because it is prime and its reverse (1369021) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1209631 - 2¹ = 1209629 is a prime.

It is a super-2 number, since 2×1209631² = 2926414312322, which contains 22 as substring.

Together with 1209629, it forms a pair of twin primes.

It is a plaindrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1209671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 604815 + 604816.

It is an arithmetic number, because the mean of its divisors is an integer number (604816).

2^1209631 is an apocalyptic number.

1209631 is a deficient number, since it is larger than the sum of its proper divisors (1).

1209631 is an equidigital number, since it uses as much as digits as its factorization.

1209631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 1209631 is about 1099.8322599379. The cubic root of 1209631 is about 106.5493904204.

The spelling of 1209631 in words is "one million, two hundred nine thousand, six hundred thirty-one".