8213257 has 4 divisors (see below), whose sum is σ = 8845060. Its totient is φ = 7581456.

The previous prime is 8213221. The next prime is 8213267. The reversal of 8213257 is 7523128.

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 2742336 + 5470921 = 1656^2 + 2339^2 .

It is a cyclic number.

It is not a de Polignac number, because 8213257 - 2¹⁵ = 8180489 is a prime.

It is a Duffinian number.

8213257 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (8213207) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 315882 + ... + 315907.

It is an arithmetic number, because the mean of its divisors is an integer number (2211265).

Almost surely, 2^8213257 is an apocalyptic number.

It is an amenable number.

8213257 is a deficient number, since it is larger than the sum of its proper divisors (631803).

8213257 is a wasteful number, since it uses less digits than its factorization.

8213257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 631802.

The product of its digits is 3360, while the sum is 28.

The square root of 8213257 is about 2865.8780504411. The cubic root of 8213257 is about 201.7615802872.

The spelling of 8213257 in words is "eight million, two hundred thirteen thousand, two hundred fifty-seven".