662640 has 80 divisors (see below), whose sum is σ = 2249856. Its totient is φ = 160000.

The previous prime is 662639. The next prime is 662647. The reversal of 662640 is 46266.

It is a tau number, because it is divible by the number of its divisors (80).

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

It is a self number, because there is not a number n which added to its sum of digits gives 662640.

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 662640.

It is not an unprimeable number, because it can be changed into a prime (662647) 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, 2515 + ... + 2765.

2⁶⁶²⁶⁴⁰ is an apocalyptic number.

662640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 662640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1124928).

662640 is an abundant number, since it is smaller than the sum of its proper divisors (1587216).

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

662640 is a wasteful number, since it uses less digits than its factorization.

662640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278 (or 272 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 662640 is about 814.0270265784. The cubic root of 662640 is about 87.1818103069.

It can be divided in two parts, 6626 and 40, that added together give a palindrome (6666).

The spelling of 662640 in words is "six hundred sixty-two thousand, six hundred forty".