642654 has 20 divisors (see below), whose sum is σ = 1440384. Its totient is φ = 214164.

The previous prime is 642623. The next prime is 642673. The reversal of 642654 is 456246.

It is a happy number.

642654 is a `hidden beast` number, since 6 + 4 + 2 + 654 = 666.

It is a super-3 number, since 3×642654³ = 796256333486226792, which contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 642654.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1822 + ... + 2145.

2⁶⁴²⁶⁵⁴ is an apocalyptic number.

642654 is an abundant number, since it is smaller than the sum of its proper divisors (797730).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642654 is a wasteful number, since it uses less digits than its factorization.

642654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3981 (or 3972 counting only the distinct ones).

The product of its digits is 5760, while the sum is 27.

The square root of 642654 is about 801.6570338992. The cubic root of 642654 is about 86.2963456026.

It can be divided in two parts, 642 and 654, that added together give a 4-th power (1296 = 6⁴).

The spelling of 642654 in words is "six hundred forty-two thousand, six hundred fifty-four".