2111531 has 2 divisors, whose sum is σ = 2111532. Its totient is φ = 2111530.

The previous prime is 2111513. The next prime is 2111533. The reversal of 2111531 is 1351112.

Together with previous prime (2111513) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2111531 is a prime.

It is a super-2 number, since 2×2111531² = 8917126327922, which contains 22 as substring.

Together with 2111533, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2111533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1055765 + 1055766.

It is an arithmetic number, because the mean of its divisors is an integer number (1055766).

2^2111531 is an apocalyptic number.

2111531 is a deficient number, since it is larger than the sum of its proper divisors (1).

2111531 is an equidigital number, since it uses as much as digits as its factorization.

2111531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30, while the sum is 14.

The square root of 2111531 is about 1453.1108010059. The cubic root of 2111531 is about 128.2918754412.

Adding to 2111531 its reverse (1351112), we get a palindrome (3462643).

The spelling of 2111531 in words is "two million, one hundred eleven thousand, five hundred thirty-one".