661795239 has 8 divisors (see below), whose sum is σ = 1008449920. Its totient is φ = 378168696.

The previous prime is 661795237. The next prime is 661795243. The reversal of 661795239 is 932597166.

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

It is not a de Polignac number, because 661795239 - 2¹ = 661795237 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 (661795237) 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, 15757009 + ... + 15757050.

It is an arithmetic number, because the mean of its divisors is an integer number (126056240).

Almost surely, 2^661795239 is an apocalyptic number.

661795239 is a deficient number, since it is larger than the sum of its proper divisors (346654681).

661795239 is a wasteful number, since it uses less digits than its factorization.

661795239 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31514069.

The product of its digits is 612360, while the sum is 48.

The square root of 661795239 is about 25725.3812216651. The cubic root of 661795239 is about 871.4474688790.

The spelling of 661795239 in words is "six hundred sixty-one million, seven hundred ninety-five thousand, two hundred thirty-nine".