642215 has 16 divisors (see below), whose sum is σ = 898560. Its totient is φ = 431520.

The previous prime is 642211. The next prime is 642217. The reversal of 642215 is 512246.

It is a happy number.

It is not a de Polignac number, because 642215 - 2² = 642211 is a prime.

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 642215.

It is not an unprimeable number, because it can be changed into a prime (642211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1910 + ... + 2220.

It is an arithmetic number, because the mean of its divisors is an integer number (56160).

2⁶⁴²²¹⁵ is an apocalyptic number.

642215 is a deficient number, since it is larger than the sum of its proper divisors (256345).

642215 is a wasteful number, since it uses less digits than its factorization.

642215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382.

The product of its digits is 480, while the sum is 20.

The square root of 642215 is about 801.3831792595. The cubic root of 642215 is about 86.2766913121.

The spelling of 642215 in words is "six hundred forty-two thousand, two hundred fifteen".