2191537 has 2 divisors, whose sum is σ = 2191538. Its totient is φ = 2191536.

The previous prime is 2191529. The next prime is 2191549. The reversal of 2191537 is 7351912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2187441 + 4096 = 1479^2 + 64^2 .

It is a cyclic number.

It is not a de Polignac number, because 2191537 - 2³ = 2191529 is a prime.

It is not a weakly prime, because it can be changed into another prime (2191507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1095768 + 1095769.

It is an arithmetic number, because the mean of its divisors is an integer number (1095769).

2^2191537 is an apocalyptic number.

It is an amenable number.

2191537 is a deficient number, since it is larger than the sum of its proper divisors (1).

2191537 is an equidigital number, since it uses as much as digits as its factorization.

2191537 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1890, while the sum is 28.

The square root of 2191537 is about 1480.3840717868. The cubic root of 2191537 is about 129.8921590865.

It can be divided in two parts, 21915 and 37, that added together give a cube (21952 = 28³).

The spelling of 2191537 in words is "two million, one hundred ninety-one thousand, five hundred thirty-seven".