2891531 has 4 divisors (see below), whose sum is σ = 2940600. Its totient is φ = 2842464.

The previous prime is 2891527. The next prime is 2891543. The reversal of 2891531 is 1351982.

2891531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2891531 - 2² = 2891527 is a prime.

It is a super-2 number, since 2×2891531² = 16721903047922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2891494 and 2891503.

It is not an unprimeable number, because it can be changed into a prime (2891501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24446 + ... + 24563.

It is an arithmetic number, because the mean of its divisors is an integer number (735150).

2^2891531 is an apocalyptic number.

2891531 is a deficient number, since it is larger than the sum of its proper divisors (49069).

2891531 is an equidigital number, since it uses as much as digits as its factorization.

2891531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49068.

The product of its digits is 2160, while the sum is 29.

The square root of 2891531 is about 1700.4502344967. The cubic root of 2891531 is about 142.4653614382.

It can be divided in two parts, 2891 and 531, that multiplied together give a square (1535121 = 1239²).

The spelling of 2891531 in words is "two million, eight hundred ninety-one thousand, five hundred thirty-one".