66077917 has 4 divisors (see below), whose sum is σ = 66095260. Its totient is φ = 66060576.

The previous prime is 66077897. The next prime is 66077923. The reversal of 66077917 is 71977066.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 60746436 + 5331481 = 7794^2 + 2309^2 .

It is a cyclic number.

It is not a de Polignac number, because 66077917 - 2⁷ = 66077789 is a prime.

It is a super-2 number, since 2×66077917² = 8732582230117778, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66077927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 192 + ... + 11497.

It is an arithmetic number, because the mean of its divisors is an integer number (16523815).

Almost surely, 2^66077917 is an apocalyptic number.

It is an amenable number.

66077917 is a deficient number, since it is larger than the sum of its proper divisors (17343).

66077917 is a wasteful number, since it uses less digits than its factorization.

66077917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17342.

The product of its (nonzero) digits is 111132, while the sum is 43.

The square root of 66077917 is about 8128.8324499894. The cubic root of 66077917 is about 404.2829704803.

The spelling of 66077917 in words is "sixty-six million, seventy-seven thousand, nine hundred seventeen".