66905560 has 16 divisors (see below), whose sum is σ = 150537600. Its totient is φ = 26762208.

The previous prime is 66905537. The next prime is 66905567. The reversal of 66905560 is 6550966.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66905567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 836280 + ... + 836359.

It is an arithmetic number, because the mean of its divisors is an integer number (9408600).

Almost surely, 2^66905560 is an apocalyptic number.

It is an amenable number.

66905560 is an abundant number, since it is smaller than the sum of its proper divisors (83632040).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66905560 is a wasteful number, since it uses less digits than its factorization.

66905560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1672650 (or 1672646 counting only the distinct ones).

The product of its (nonzero) digits is 48600, while the sum is 37.

The square root of 66905560 is about 8179.5818964052. The cubic root of 66905560 is about 405.9638881711.

The spelling of 66905560 in words is "sixty-six million, nine hundred five thousand, five hundred sixty".