661177487 has 8 divisors (see below), whose sum is σ = 665995200. Its totient is φ = 656377344.

The previous prime is 661177483. The next prime is 661177501. The reversal of 661177487 is 784771166.

It is a happy number.

661177487 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 661177487 - 2² = 661177483 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661177483) 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, 76439 + ... + 84647.

It is an arithmetic number, because the mean of its divisors is an integer number (83249400).

Almost surely, 2^661177487 is an apocalyptic number.

661177487 is a deficient number, since it is larger than the sum of its proper divisors (4817713).

661177487 is a wasteful number, since it uses less digits than its factorization.

661177487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8785.

The product of its digits is 395136, while the sum is 47.

The square root of 661177487 is about 25713.3717547894. The cubic root of 661177487 is about 871.1762339231.

The spelling of 661177487 in words is "six hundred sixty-one million, one hundred seventy-seven thousand, four hundred eighty-seven".