67640640 has 56 divisors (see below), whose sum is σ = 214762080. Its totient is φ = 18037248.

The previous prime is 67640633. The next prime is 67640647. The reversal of 67640640 is 4604676.

It is an interprime number because it is at equal distance from previous prime (67640633) and next prime (67640647).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67640647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34270 + ... + 36189.

Almost surely, 2^67640640 is an apocalyptic number.

67640640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

67640640 is an abundant number, since it is smaller than the sum of its proper divisors (147121440).

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

67640640 is a wasteful number, since it uses less digits than its factorization.

67640640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70479 (or 70469 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 33.

The square root of 67640640 is about 8224.3929867194. The cubic root of 67640640 is about 407.4452283142.

The spelling of 67640640 in words is "sixty-seven million, six hundred forty thousand, six hundred forty".