642626 has 4 divisors (see below), whose sum is σ = 963942. Its totient is φ = 321312.

The previous prime is 642623. The next prime is 642673. The reversal of 642626 is 626246.

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., 638401 + 4225 = 799^2 + 65^2 .

It is a junction number, because it is equal to n+sod(n) for n = 642595 and 642604.

It is not an unprimeable number, because it can be changed into a prime (642623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160655 + ... + 160658.

2⁶⁴²⁶²⁶ is an apocalyptic number.

642626 is a deficient number, since it is larger than the sum of its proper divisors (321316).

642626 is a wasteful number, since it uses less digits than its factorization.

642626 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321315.

The product of its digits is 3456, while the sum is 26.

The square root of 642626 is about 801.6395698816. The cubic root of 642626 is about 86.2950922932.

The spelling of 642626 in words is "six hundred forty-two thousand, six hundred twenty-six".