642428 has 24 divisors (see below), whose sum is σ = 1209600. Its totient is φ = 297648.

The previous prime is 642427. The next prime is 642457. The reversal of 642428 is 824246.

It is a junction number, because it is equal to n+sod(n) for n = 642397 and 642406.

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 642428.

It is not an unprimeable number, because it can be changed into a prime (642427) 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, 5951 + ... + 6057.

It is an arithmetic number, because the mean of its divisors is an integer number (50400).

2⁶⁴²⁴²⁸ is an apocalyptic number.

It is an amenable number.

642428 is a deficient number, since it is larger than the sum of its proper divisors (567172).

642428 is a wasteful number, since it uses less digits than its factorization.

642428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209 (or 207 counting only the distinct ones).

The product of its digits is 3072, while the sum is 26.

The square root of 642428 is about 801.5160634697. The cubic root of 642428 is about 86.2862285667.

The spelling of 642428 in words is "six hundred forty-two thousand, four hundred twenty-eight".