66900017 has 2 divisors, whose sum is σ = 66900018. Its totient is φ = 66900016.

The previous prime is 66899999. The next prime is 66900023. The reversal of 66900017 is 71000966.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60902416 + 5997601 = 7804^2 + 2449^2 .

It is a cyclic number.

It is not a de Polignac number, because 66900017 - 2¹² = 66895921 is a prime.

It is a super-2 number, since 2×66900017² = 8951224549200578, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66900037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33450008 + 33450009.

It is an arithmetic number, because the mean of its divisors is an integer number (33450009).

Almost surely, 2^66900017 is an apocalyptic number.

It is an amenable number.

66900017 is a deficient number, since it is larger than the sum of its proper divisors (1).

66900017 is an equidigital number, since it uses as much as digits as its factorization.

66900017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2268, while the sum is 29.

The square root of 66900017 is about 8179.2430578874. The cubic root of 66900017 is about 405.9526767462.

The spelling of 66900017 in words is "sixty-six million, nine hundred thousand, seventeen".