1643226631 has 2 divisors, whose sum is σ = 1643226632. Its totient is φ = 1643226630.

The previous prime is 1643226619. The next prime is 1643226667. The reversal of 1643226631 is 1366223461.

It is a weak prime.

It is an emirp because it is prime and its reverse (1366223461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1643226631 - 2⁷ = 1643226503 is a prime.

It is a super-2 number, since 2×1643226631² = 5400387521655220322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1643226691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821613315 + 821613316.

It is an arithmetic number, because the mean of its divisors is an integer number (821613316).

Almost surely, 2^1643226631 is an apocalyptic number.

1643226631 is a deficient number, since it is larger than the sum of its proper divisors (1).

1643226631 is an equidigital number, since it uses as much as digits as its factorization.

1643226631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31104, while the sum is 34.

The square root of 1643226631 is about 40536.7318736970. The cubic root of 1643226631 is about 1180.0465918116.

The spelling of 1643226631 in words is "one billion, six hundred forty-three million, two hundred twenty-six thousand, six hundred thirty-one".