642790 has 8 divisors (see below), whose sum is σ = 1157040. Its totient is φ = 257112.

The previous prime is 642779. The next prime is 642791. The reversal of 642790 is 97246.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642791) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32130 + ... + 32149.

It is an arithmetic number, because the mean of its divisors is an integer number (144630).

2⁶⁴²⁷⁹⁰ is an apocalyptic number.

642790 is a deficient number, since it is larger than the sum of its proper divisors (514250).

642790 is a wasteful number, since it uses less digits than its factorization.

642790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64286.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 642790 is about 801.7418537160. The cubic root of 642790 is about 86.3024325873.

The spelling of 642790 in words is "six hundred forty-two thousand, seven hundred ninety".