66487761 has 12 divisors (see below), whose sum is σ = 98271888. Its totient is φ = 43294104.

The previous prime is 66487739. The next prime is 66487763. The reversal of 66487761 is 16778466.

It is a de Polignac number, because none of the positive numbers 2^k-66487761 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66487763) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 85515 + ... + 86288.

It is an arithmetic number, because the mean of its divisors is an integer number (8189324).

Almost surely, 2^66487761 is an apocalyptic number.

It is an amenable number.

66487761 is a deficient number, since it is larger than the sum of its proper divisors (31784127).

66487761 is a wasteful number, since it uses less digits than its factorization.

66487761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171852 (or 171849 counting only the distinct ones).

The product of its digits is 338688, while the sum is 45.

The square root of 66487761 is about 8154.0027593814. The cubic root of 66487761 is about 405.1170946286.

Subtracting from 66487761 its sum of digits (45), we obtain a square (66487716 = 8154²).

The spelling of 66487761 in words is "sixty-six million, four hundred eighty-seven thousand, seven hundred sixty-one".