212131566 has 48 divisors (see below), whose sum is σ = 469857024. Its totient is φ = 69153552.

The previous prime is 212131547. The next prime is 212131567. The reversal of 212131566 is 665131212.

It is a super-2 number, since 2×212131566² = 89999602587224712, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212131567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 159195 + ... + 160521.

It is an arithmetic number, because the mean of its divisors is an integer number (9788688).

Almost surely, 2^212131566 is an apocalyptic number.

212131566 is an abundant number, since it is smaller than the sum of its proper divisors (257725458).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

212131566 is a wasteful number, since it uses less digits than its factorization.

212131566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1525 (or 1522 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 212131566 is about 14564.7370728070. The cubic root of 212131566 is about 596.3965181902.

Adding to 212131566 its reverse (665131212), we get a palindrome (877262778).

The spelling of 212131566 in words is "two hundred twelve million, one hundred thirty-one thousand, five hundred sixty-six".