66761964 has 36 divisors (see below), whose sum is σ = 169381576. Its totient is φ = 22171968.

The previous prime is 66761951. The next prime is 66761969. The reversal of 66761964 is 46916766.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66761969) 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 11 ways as a sum of consecutive naturals, for example, 6912 + ... + 13464.

Almost surely, 2^66761964 is an apocalyptic number.

It is an amenable number.

66761964 is an abundant number, since it is smaller than the sum of its proper divisors (102619612).

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

66761964 is a wasteful number, since it uses less digits than its factorization.

66761964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6846 (or 6841 counting only the distinct ones).

The product of its digits is 326592, while the sum is 45.

The square root of 66761964 is about 8170.7994712880. The cubic root of 66761964 is about 405.6732469282.

The spelling of 66761964 in words is "sixty-six million, seven hundred sixty-one thousand, nine hundred sixty-four".