661015617 has 8 divisors (see below), whose sum is σ = 883243296. Its totient is φ = 439732512.

The previous prime is 661015603. The next prime is 661015633. The reversal of 661015617 is 716510166.

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

It is not a de Polignac number, because 661015617 - 2⁸ = 661015361 is a prime.

It is not an unprimeable number, because it can be changed into a prime (661015517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 234508 + ... + 237309.

It is an arithmetic number, because the mean of its divisors is an integer number (110405412).

Almost surely, 2^661015617 is an apocalyptic number.

It is an amenable number.

661015617 is a deficient number, since it is larger than the sum of its proper divisors (222227679).

661015617 is a wasteful number, since it uses less digits than its factorization.

661015617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472287.

The product of its (nonzero) digits is 7560, while the sum is 33.

The square root of 661015617 is about 25710.2239780209. The cubic root of 661015617 is about 871.1051341003.

The spelling of 661015617 in words is "six hundred sixty-one million, fifteen thousand, six hundred seventeen".