642653 has 8 divisors (see below), whose sum is σ = 720480. Its totient is φ = 568080.

The previous prime is 642623. The next prime is 642673. The reversal of 642653 is 356246.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642613) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 383 + ... + 1196.

It is an arithmetic number, because the mean of its divisors is an integer number (90060).

2⁶⁴²⁶⁵³ is an apocalyptic number.

It is an amenable number.

642653 is a deficient number, since it is larger than the sum of its proper divisors (77827).

642653 is a wasteful number, since it uses less digits than its factorization.

642653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1627.

The product of its digits is 4320, while the sum is 26.

The square root of 642653 is about 801.6564101908. The cubic root of 642653 is about 86.2963008422.

Adding to 642653 its reverse (356246), we get a palindrome (998899).

The spelling of 642653 in words is "six hundred forty-two thousand, six hundred fifty-three".