67221997 has 2 divisors, whose sum is σ = 67221998. Its totient is φ = 67221996.

The previous prime is 67221983. The next prime is 67222003. The reversal of 67221997 is 79912276.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58155876 + 9066121 = 7626^2 + 3011^2 .

It is a cyclic number.

It is not a de Polignac number, because 67221997 - 2¹¹ = 67219949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (67221197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33610998 + 33610999.

It is an arithmetic number, because the mean of its divisors is an integer number (33610999).

Almost surely, 2^67221997 is an apocalyptic number.

It is an amenable number.

67221997 is a deficient number, since it is larger than the sum of its proper divisors (1).

67221997 is an equidigital number, since it uses as much as digits as its factorization.

67221997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 95256, while the sum is 43.

The square root of 67221997 is about 8198.9021826096. The cubic root of 67221997 is about 406.6028983442.

The spelling of 67221997 in words is "sixty-seven million, two hundred twenty-one thousand, nine hundred ninety-seven".