661067017 has 4 divisors (see below), whose sum is σ = 711918340. Its totient is φ = 610215696.

The previous prime is 661066979. The next prime is 661067021. The reversal of 661067017 is 710760166.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 409495696 + 251571321 = 20236^2 + 15861^2 .

It is a cyclic number.

It is not a de Polignac number, because 661067017 - 2²⁷ = 526849289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661067087) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25425642 + ... + 25425667.

It is an arithmetic number, because the mean of its divisors is an integer number (177979585).

Almost surely, 2^661067017 is an apocalyptic number.

It is an amenable number.

661067017 is a deficient number, since it is larger than the sum of its proper divisors (50851323).

661067017 is a wasteful number, since it uses less digits than its factorization.

661067017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50851322.

The product of its (nonzero) digits is 10584, while the sum is 34.

The square root of 661067017 is about 25711.2235609276. The cubic root of 661067017 is about 871.1277123078.

The spelling of 661067017 in words is "six hundred sixty-one million, sixty-seven thousand, seventeen".