67638240 has 240 divisors, whose sum is σ = 253571472. Its totient is φ = 16920576.

The previous prime is 67638209. The next prime is 67638247. The reversal of 67638240 is 4283676.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 67638195 and 67638204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67638247) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 220167 + ... + 220473.

Almost surely, 2^67638240 is an apocalyptic number.

67638240 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 67638240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126785736).

67638240 is an abundant number, since it is smaller than the sum of its proper divisors (185933232).

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

67638240 is a wasteful number, since it uses less digits than its factorization.

67638240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351 (or 334 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 67638240 is about 8224.2470780005. The cubic root of 67638240 is about 407.4404093172.

The spelling of 67638240 in words is "sixty-seven million, six hundred thirty-eight thousand, two hundred forty".