247642 has 4 divisors (see below), whose sum is σ = 371466. Its totient is φ = 123820.

The previous prime is 247633. The next prime is 247649. The reversal of 247642 is 246742.

247642 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in only one way, i.e., 241081 + 6561 = 491^2 + 81^2 .

It is a super-2 number, since 2×247642² = 122653120328, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (247649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61909 + ... + 61912.

2²⁴⁷⁶⁴² is an apocalyptic number.

247642 is a deficient number, since it is larger than the sum of its proper divisors (123824).

247642 is a wasteful number, since it uses less digits than its factorization.

247642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123823.

The product of its digits is 2688, while the sum is 25.

The square root of 247642 is about 497.6364134587. The cubic root of 247642 is about 62.7973669227.

Subtracting from 247642 its reverse (246742), we obtain a square (900 = 30²).

The spelling of 247642 in words is "two hundred forty-seven thousand, six hundred forty-two".