687257243 has 4 divisors (see below), whose sum is σ = 689296920. Its totient is φ = 685217568.

The previous prime is 687257237. The next prime is 687257251. The reversal of 687257243 is 342752786.

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

It is a cyclic number.

It is not a de Polignac number, because 687257243 - 2¹⁴ = 687240859 is a prime.

It is a super-2 number, since 2×687257243² = 944645036111922098, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 687257194 and 687257203.

It is not an unprimeable number, because it can be changed into a prime (687257213) 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, 1019333 + ... + 1020006.

It is an arithmetic number, because the mean of its divisors is an integer number (172324230).

Almost surely, 2^687257243 is an apocalyptic number.

687257243 is a deficient number, since it is larger than the sum of its proper divisors (2039677).

687257243 is a wasteful number, since it uses less digits than its factorization.

687257243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2039676.

The product of its digits is 564480, while the sum is 44.

The square root of 687257243 is about 26215.5916011827. The cubic root of 687257243 is about 882.4831907816.

The spelling of 687257243 in words is "six hundred eighty-seven million, two hundred fifty-seven thousand, two hundred forty-three".