640115 has 8 divisors (see below), whose sum is σ = 877920. Its totient is φ = 438912.

The previous prime is 640109. The next prime is 640121. The reversal of 640115 is 511046.

It is a happy number.

640115 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (640109) and next prime (640121).

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

It is a cyclic number.

It is not a de Polignac number, because 640115 - 2⁴ = 640099 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 640093 and 640102.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9110 + ... + 9179.

It is an arithmetic number, because the mean of its divisors is an integer number (109740).

2⁶⁴⁰¹¹⁵ is an apocalyptic number.

640115 is a deficient number, since it is larger than the sum of its proper divisors (237805).

640115 is a wasteful number, since it uses less digits than its factorization.

640115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18301.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 640115 is about 800.0718717715. The cubic root of 640115 is about 86.1825489586.

The spelling of 640115 in words is "six hundred forty thousand, one hundred fifteen".