667137561 has 8 divisors (see below), whose sum is σ = 910203360. Its totient is φ = 434415072.

The previous prime is 667137473. The next prime is 667137571. The reversal of 667137561 is 165731766.

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

It is not a de Polignac number, because 667137561 - 2¹⁴ = 667121177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (667137571) 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, 2585676 + ... + 2585933.

It is an arithmetic number, because the mean of its divisors is an integer number (113775420).

Almost surely, 2^667137561 is an apocalyptic number.

It is an amenable number.

667137561 is a deficient number, since it is larger than the sum of its proper divisors (243065799).

667137561 is a wasteful number, since it uses less digits than its factorization.

667137561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5171655.

The product of its digits is 158760, while the sum is 42.

The square root of 667137561 is about 25829.0061945867. The cubic root of 667137561 is about 873.7860983733.

The spelling of 667137561 in words is "six hundred sixty-seven million, one hundred thirty-seven thousand, five hundred sixty-one".