212643531 has 24 divisors (see below), whose sum is σ = 325840320. Its totient is φ = 133168896.

The previous prime is 212643521. The next prime is 212643553. The reversal of 212643531 is 135346212.

212643531 is a `hidden beast` number, since 2 + 12 + 643 + 5 + 3 + 1 = 666.

It is not a de Polignac number, because 212643531 - 2¹⁸ = 212381387 is a prime.

It is a super-2 number, since 2×212643531² = 90434542552295922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 212643495 and 212643504.

It is not an unprimeable number, because it can be changed into a prime (212643521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 109041 + ... + 110973.

It is an arithmetic number, because the mean of its divisors is an integer number (13576680).

Almost surely, 2^212643531 is an apocalyptic number.

212643531 is a deficient number, since it is larger than the sum of its proper divisors (113196789).

212643531 is a wasteful number, since it uses less digits than its factorization.

212643531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2675 (or 2672 counting only the distinct ones).

The product of its digits is 4320, while the sum is 27.

The square root of 212643531 is about 14582.3019787686. The cubic root of 212643531 is about 596.8759201068.

Adding to 212643531 its reverse (135346212), we get a palindrome (347989743).

The spelling of 212643531 in words is "two hundred twelve million, six hundred forty-three thousand, five hundred thirty-one".