67640220 has 36 divisors (see below), whose sum is σ = 205175880. Its totient is φ = 18037344.

The previous prime is 67640219. The next prime is 67640227. The reversal of 67640220 is 2204676.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67640227) 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, 187710 + ... + 188069.

It is an arithmetic number, because the mean of its divisors is an integer number (5699330).

Almost surely, 2^67640220 is an apocalyptic number.

67640220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

67640220 is an abundant number, since it is smaller than the sum of its proper divisors (137535660).

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

67640220 is a wasteful number, since it uses less digits than its factorization.

67640220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375794 (or 375789 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 67640220 is about 8224.3674528805. The cubic root of 67640220 is about 407.4443849979. Note that the first 3 decimals are identical.

Adding to 67640220 its reverse (2204676), we get a palindrome (69844896).

The spelling of 67640220 in words is "sixty-seven million, six hundred forty thousand, two hundred twenty".