67221387 has 16 divisors (see below), whose sum is σ = 103918080. Its totient is φ = 42865416.

The previous prime is 67221367. The next prime is 67221397. The reversal of 67221387 is 78312276.

It is not a de Polignac number, because 67221387 - 2⁸ = 67221131 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (67221307) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53503 + ... + 54744.

It is an arithmetic number, because the mean of its divisors is an integer number (6494880).

Almost surely, 2^67221387 is an apocalyptic number.

67221387 is a deficient number, since it is larger than the sum of its proper divisors (36696693).

67221387 is a wasteful number, since it uses less digits than its factorization.

67221387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108279 (or 108273 counting only the distinct ones).

The product of its digits is 28224, while the sum is 36.

The square root of 67221387 is about 8198.8649824229. The cubic root of 67221387 is about 406.6016684466.

The spelling of 67221387 in words is "sixty-seven million, two hundred twenty-one thousand, three hundred eighty-seven".