639480 has 48 divisors (see below), whose sum is σ = 1945080. Its totient is φ = 168192.

The previous prime is 639451. The next prime is 639487. The reversal of 639480 is 84936.

639480 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639487) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8724 + ... + 8796.

2⁶³⁹⁴⁸⁰ is an apocalyptic number.

639480 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 639480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (972540).

639480 is an abundant number, since it is smaller than the sum of its proper divisors (1305600).

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

639480 is a wasteful number, since it uses less digits than its factorization.

639480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160 (or 83 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 639480 is about 799.6749339575. The cubic root of 639480 is about 86.1540415681.

Multiplying 639480 by its sum of digits (30), we get a square (19184400 = 4380²).

639480 divided by its sum of digits (30) gives a square (21316 = 146²).

The spelling of 639480 in words is "six hundred thirty-nine thousand, four hundred eighty".