8921257 has 4 divisors (see below), whose sum is σ = 9043540. Its totient is φ = 8798976.

The previous prime is 8921249. The next prime is 8921261. The reversal of 8921257 is 7521298.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2062096 + 6859161 = 1436^2 + 2619^2 .

It is a cyclic number.

It is not a de Polignac number, because 8921257 - 2³ = 8921249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8921207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61032 + ... + 61177.

It is an arithmetic number, because the mean of its divisors is an integer number (2260885).

Almost surely, 2^8921257 is an apocalyptic number.

It is an amenable number.

8921257 is a deficient number, since it is larger than the sum of its proper divisors (122283).

8921257 is a wasteful number, since it uses less digits than its factorization.

8921257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122282.

The product of its digits is 10080, while the sum is 34.

The square root of 8921257 is about 2986.8473345653. The cubic root of 8921257 is about 207.3999672670.

The spelling of 8921257 in words is "eight million, nine hundred twenty-one thousand, two hundred fifty-seven".