8438640 has 80 divisors (see below), whose sum is σ = 29902848. Its totient is φ = 1928448.

The previous prime is 8438629. The next prime is 8438653. The reversal of 8438640 is 468348.

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

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 832 + ... + 4191.

Almost surely, 2^8438640 is an apocalyptic number.

8438640 is a gapful number since it is divisible by the number (80) 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 8438640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14951424).

8438640 is an abundant number, since it is smaller than the sum of its proper divisors (21464208).

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

8438640 is a wasteful number, since it uses less digits than its factorization.

8438640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5046 (or 5040 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 33.

The square root of 8438640 is about 2904.9337341840. The cubic root of 8438640 is about 203.5904895312.

The spelling of 8438640 in words is "eight million, four hundred thirty-eight thousand, six hundred forty".