66169639 has 2 divisors, whose sum is σ = 66169640. Its totient is φ = 66169638.

The previous prime is 66169633. The next prime is 66169651. The reversal of 66169639 is 93696166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66169639 - 2⁷ = 66169511 is a prime.

It is a super-2 number, since 2×66169639² = 8756842250780642, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66169633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33084819 + 33084820.

It is an arithmetic number, because the mean of its divisors is an integer number (33084820).

Almost surely, 2^66169639 is an apocalyptic number.

66169639 is a deficient number, since it is larger than the sum of its proper divisors (1).

66169639 is an equidigital number, since it uses as much as digits as its factorization.

66169639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 314928, while the sum is 46.

The square root of 66169639 is about 8134.4722631527. The cubic root of 66169639 is about 404.4699441824.

The spelling of 66169639 in words is "sixty-six million, one hundred sixty-nine thousand, six hundred thirty-nine".