2157247 has 2 divisors, whose sum is σ = 2157248. Its totient is φ = 2157246.

The previous prime is 2157229. The next prime is 2157251. The reversal of 2157247 is 7427512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2157247 - 2⁷ = 2157119 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2157257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1078623 + 1078624.

It is an arithmetic number, because the mean of its divisors is an integer number (1078624).

2^2157247 is an apocalyptic number.

2157247 is a deficient number, since it is larger than the sum of its proper divisors (1).

2157247 is an equidigital number, since it uses as much as digits as its factorization.

2157247 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3920, while the sum is 28.

The square root of 2157247 is about 1468.7569574303. The cubic root of 2157247 is about 129.2111399175.

The spelling of 2157247 in words is "two million, one hundred fifty-seven thousand, two hundred forty-seven".