212511491 has 2 divisors, whose sum is σ = 212511492. Its totient is φ = 212511490.

The previous prime is 212511473. The next prime is 212511493. The reversal of 212511491 is 194115212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 212511491 - 2⁶ = 212511427 is a prime.

It is a super-3 number, since 3×212511491³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 212511493, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 212511491.

It is not a weakly prime, because it can be changed into another prime (212511493) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106255745 + 106255746.

It is an arithmetic number, because the mean of its divisors is an integer number (106255746).

Almost surely, 2^212511491 is an apocalyptic number.

212511491 is a deficient number, since it is larger than the sum of its proper divisors (1).

212511491 is an equidigital number, since it uses as much as digits as its factorization.

212511491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 720, while the sum is 26.

The square root of 212511491 is about 14577.7738698335. The cubic root of 212511491 is about 596.7523520956.

The spelling of 212511491 in words is "two hundred twelve million, five hundred eleven thousand, four hundred ninety-one".