212145631 has 2 divisors, whose sum is σ = 212145632. Its totient is φ = 212145630.

The previous prime is 212145613. The next prime is 212145667. The reversal of 212145631 is 136541212.

It is a happy number.

Together with previous prime (212145613) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 212145631 - 2⁵ = 212145599 is a prime.

It is a super-3 number, since 3×212145631³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is equal to p_11713426 and since 212145631 and 11713426 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 212145596 and 212145605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212145671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106072815 + 106072816.

It is an arithmetic number, because the mean of its divisors is an integer number (106072816).

Almost surely, 2^212145631 is an apocalyptic number.

212145631 is a deficient number, since it is larger than the sum of its proper divisors (1).

212145631 is an equidigital number, since it uses as much as digits as its factorization.

212145631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 25.

The square root of 212145631 is about 14565.2199090848. The cubic root of 212145631 is about 596.4096988966.

Adding to 212145631 its reverse (136541212), we get a palindrome (348686843).

The spelling of 212145631 in words is "two hundred twelve million, one hundred forty-five thousand, six hundred thirty-one".