66167639 has 2 divisors, whose sum is σ = 66167640. Its totient is φ = 66167638.

The previous prime is 66167617. The next prime is 66167641. The reversal of 66167639 is 93676166.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66167639 is a prime.

Together with 66167641, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66167639.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66167839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33083819 + 33083820.

It is an arithmetic number, because the mean of its divisors is an integer number (33083820).

Almost surely, 2^66167639 is an apocalyptic number.

66167639 is a deficient number, since it is larger than the sum of its proper divisors (1).

66167639 is an equidigital number, since it uses as much as digits as its factorization.

66167639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 244944, while the sum is 44.

The square root of 66167639 is about 8134.3493286187. The cubic root of 66167639 is about 404.4658690604.

The spelling of 66167639 in words is "sixty-six million, one hundred sixty-seven thousand, six hundred thirty-nine".