66761505 has 48 divisors (see below), whose sum is σ = 120326544. Its totient is φ = 34214400.

The previous prime is 66761491. The next prime is 66761531. The reversal of 66761505 is 50516766.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 17438976 + 49322529 = 4176^2 + 7023^2 .

It is not a de Polignac number, because 66761505 - 2¹⁵ = 66728737 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 66761505.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 167967 + ... + 168363.

It is an arithmetic number, because the mean of its divisors is an integer number (2506803).

Almost surely, 2^66761505 is an apocalyptic number.

It is an amenable number.

66761505 is a deficient number, since it is larger than the sum of its proper divisors (53565039).

66761505 is a wasteful number, since it uses less digits than its factorization.

66761505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 546 (or 543 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 36.

The square root of 66761505 is about 8170.7713834130. The cubic root of 66761505 is about 405.6723172350.

The spelling of 66761505 in words is "sixty-six million, seven hundred sixty-one thousand, five hundred five".