26191657 has 2 divisors, whose sum is σ = 26191658. Its totient is φ = 26191656.

The previous prime is 26191619. The next prime is 26191663. The reversal of 26191657 is 75619162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23270976 + 2920681 = 4824^2 + 1709^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26191657 is a prime.

It is not a weakly prime, because it can be changed into another prime (26198657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13095828 + 13095829.

It is an arithmetic number, because the mean of its divisors is an integer number (13095829).

Almost surely, 2^26191657 is an apocalyptic number.

It is an amenable number.

26191657 is a deficient number, since it is larger than the sum of its proper divisors (1).

26191657 is an equidigital number, since it uses as much as digits as its factorization.

26191657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22680, while the sum is 37.

The square root of 26191657 is about 5117.7785219761. The cubic root of 26191657 is about 296.9757525731.

The spelling of 26191657 in words is "twenty-six million, one hundred ninety-one thousand, six hundred fifty-seven".