66520069 has 8 divisors (see below), whose sum is σ = 82934208. Its totient is φ = 51833760.

The previous prime is 66520063. The next prime is 66520151. The reversal of 66520069 is 96002566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66520069 - 2³ = 66520061 is a prime.

It is a super-2 number, since 2×66520069² = 8849839159529522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66520061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 431872 + ... + 432025.

It is an arithmetic number, because the mean of its divisors is an integer number (10366776).

Almost surely, 2^66520069 is an apocalyptic number.

It is an amenable number.

66520069 is a deficient number, since it is larger than the sum of its proper divisors (16414139).

66520069 is a wasteful number, since it uses less digits than its factorization.

66520069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 863915.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 66520069 is about 8155.9836316658. The cubic root of 66520069 is about 405.1827027117.

The spelling of 66520069 in words is "sixty-six million, five hundred twenty thousand, sixty-nine".