640262 has 32 divisors (see below), whose sum is σ = 1209600. Its totient is φ = 247968.

The previous prime is 640261. The next prime is 640267. The reversal of 640262 is 262046.

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 640262.

It is not an unprimeable number, because it can be changed into a prime (640261) 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, 7673 + ... + 7755.

It is an arithmetic number, because the mean of its divisors is an integer number (37800).

2⁶⁴⁰²⁶² is an apocalyptic number.

640262 is a deficient number, since it is larger than the sum of its proper divisors (569338).

640262 is a wasteful number, since it uses less digits than its factorization.

640262 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140.

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 640262 is about 800.1637332446. The cubic root of 640262 is about 86.1891456196.

The spelling of 640262 in words is "six hundred forty thousand, two hundred sixty-two".