640248 has 64 divisors (see below), whose sum is σ = 1896960. Its totient is φ = 176256.

The previous prime is 640247. The next prime is 640249. The reversal of 640248 is 842046.

640248 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 (640247) and next prime (640249).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6165 + ... + 6267.

It is an arithmetic number, because the mean of its divisors is an integer number (29640).

2⁶⁴⁰²⁴⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (948480).

640248 is an abundant number, since it is smaller than the sum of its proper divisors (1256712).

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

640248 is a wasteful number, since it uses less digits than its factorization.

640248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 152 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 640248 is about 800.1549849873. The cubic root of 640248 is about 86.1885174097.

It can be divided in two parts, 640 and 248, that added together give a palindrome (888).

The spelling of 640248 in words is "six hundred forty thousand, two hundred forty-eight".