221634631 has 2 divisors, whose sum is σ = 221634632. Its totient is φ = 221634630.

The previous prime is 221634619. The next prime is 221634641. The reversal of 221634631 is 136436122.

221634631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221634631 - 2¹⁷ = 221503559 is a prime.

It is a super-2 number, since 2×221634631² = 98243819317012322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 221634631.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221634641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110817315 + 110817316.

It is an arithmetic number, because the mean of its divisors is an integer number (110817316).

Almost surely, 2^221634631 is an apocalyptic number.

221634631 is a deficient number, since it is larger than the sum of its proper divisors (1).

221634631 is an equidigital number, since it uses as much as digits as its factorization.

221634631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5184, while the sum is 28.

The square root of 221634631 is about 14887.3983959589. The cubic root of 221634631 is about 605.1725309909.

The spelling of 221634631 in words is "two hundred twenty-one million, six hundred thirty-four thousand, six hundred thirty-one".