661316267 has 4 divisors (see below), whose sum is σ = 662479080. Its totient is φ = 660153456.

The previous prime is 661316251. The next prime is 661316287. The reversal of 661316267 is 762613166.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 661316267 - 2⁴ = 661316251 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 661316267.

It is not an unprimeable number, because it can be changed into a prime (661316287) 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, 580553 + ... + 581690.

It is an arithmetic number, because the mean of its divisors is an integer number (165619770).

Almost surely, 2^661316267 is an apocalyptic number.

661316267 is a deficient number, since it is larger than the sum of its proper divisors (1162813).

661316267 is a wasteful number, since it uses less digits than its factorization.

661316267 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1162812.

The product of its digits is 54432, while the sum is 38.

The square root of 661316267 is about 25716.0702091124. The cubic root of 661316267 is about 871.2371824491.

The spelling of 661316267 in words is "six hundred sixty-one million, three hundred sixteen thousand, two hundred sixty-seven".