2156731 has 2 divisors, whose sum is σ = 2156732. Its totient is φ = 2156730.

The previous prime is 2156719. The next prime is 2156753. The reversal of 2156731 is 1376512.

2156731 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2156731 - 2⁵ = 2156699 is a prime.

It is a super-2 number, since 2×2156731² = 9302977212722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2156696 and 2156705.

It is not a weakly prime, because it can be changed into another prime (2156711) 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 as a sum of consecutive naturals, namely, 1078365 + 1078366.

It is an arithmetic number, because the mean of its divisors is an integer number (1078366).

2^2156731 is an apocalyptic number.

2156731 is a deficient number, since it is larger than the sum of its proper divisors (1).

2156731 is an equidigital number, since it uses as much as digits as its factorization.

2156731 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1260, while the sum is 25.

The square root of 2156731 is about 1468.5812881826. The cubic root of 2156731 is about 129.2008369303.

The spelling of 2156731 in words is "two million, one hundred fifty-six thousand, seven hundred thirty-one".