642942 has 24 divisors (see below), whose sum is σ = 1454544. Its totient is φ = 204864.

The previous prime is 642937. The next prime is 642947. The reversal of 642942 is 249246.

It is an interprime number because it is at equal distance from previous prime (642937) and next prime (642947).

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

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 642942.

It is not an unprimeable number, because it can be changed into a prime (642947) by changing a digit.

642942 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 363 + ... + 1190.

It is an arithmetic number, because the mean of its divisors is an integer number (60606).

2⁶⁴²⁹⁴² is an apocalyptic number.

642942 is an abundant number, since it is smaller than the sum of its proper divisors (811602).

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

642942 is a wasteful number, since it uses less digits than its factorization.

642942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1584 (or 1581 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 642942 is about 801.8366417170. The cubic root of 642942 is about 86.3092346719.

The spelling of 642942 in words is "six hundred forty-two thousand, nine hundred forty-two".