642634 has 16 divisors (see below), whose sum is σ = 1047816. Its totient is φ = 294400.

The previous prime is 642623. The next prime is 642673. The reversal of 642634 is 436246.

642634 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 426409 + 216225 = 653^2 + 465^2 .

It is a junction number, because it is equal to n+sod(n) for n = 642599 and 642608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1164 + ... + 1624.

2⁶⁴²⁶³⁴ is an apocalyptic number.

642634 is a deficient number, since it is larger than the sum of its proper divisors (405182).

642634 is a wasteful number, since it uses less digits than its factorization.

642634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521.

The product of its digits is 3456, while the sum is 25.

The square root of 642634 is about 801.6445596397. The cubic root of 642634 is about 86.2954503853.

The spelling of 642634 in words is "six hundred forty-two thousand, six hundred thirty-four".