1263631 has 2 divisors, whose sum is σ = 1263632. Its totient is φ = 1263630.

The previous prime is 1263629. The next prime is 1263659. The reversal of 1263631 is 1363621.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1263631 - 2¹ = 1263629 is a prime.

It is a super-2 number, since 2×1263631² = 3193526608322, which contains 22 as substring.

Together with 1263629, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1263331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 631815 + 631816.

It is an arithmetic number, because the mean of its divisors is an integer number (631816).

2^1263631 is an apocalyptic number.

1263631 is a deficient number, since it is larger than the sum of its proper divisors (1).

1263631 is an equidigital number, since it uses as much as digits as its factorization.

1263631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 648, while the sum is 22.

The square root of 1263631 is about 1124.1134284404. The cubic root of 1263631 is about 108.1118810862. Note that the first 3 decimals are identical.

It can be divided in two parts, 1263 and 631, that multiplied together give a triangular number (796953 = T₁₂₆₂).

The spelling of 1263631 in words is "one million, two hundred sixty-three thousand, six hundred thirty-one".