639788148 has 36 divisors (see below), whose sum is σ = 1687559328. Its totient is φ = 203990160.

The previous prime is 639788141. The next prime is 639788161. The reversal of 639788148 is 841887936.

It is a tau number, because it is divible by the number of its divisors (36).

It is a junction number, because it is equal to n+sod(n) for n = 639788094 and 639788103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639788141) 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, 385518 + ... + 387173.

It is an arithmetic number, because the mean of its divisors is an integer number (46876648).

Almost surely, 2^639788148 is an apocalyptic number.

It is an amenable number.

639788148 is an abundant number, since it is smaller than the sum of its proper divisors (1047771180).

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

639788148 is a wasteful number, since it uses less digits than its factorization.

639788148 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 772724 (or 772719 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 54.

The square root of 639788148 is about 25294.0338419952. The cubic root of 639788148 is about 861.6787777485.

It can be divided in two parts, 639788 and 148, that added together give a palindrome (639936).

The spelling of 639788148 in words is "six hundred thirty-nine million, seven hundred eighty-eight thousand, one hundred forty-eight".