661512535 has 8 divisors (see below), whose sum is σ = 794487600. Its totient is φ = 528761664.

The previous prime is 661512521. The next prime is 661512539. The reversal of 661512535 is 535215166.

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

It is a cyclic number.

It is not a de Polignac number, because 661512535 - 2⁹ = 661512023 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 661512535.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661512539) 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, 49485 + ... + 61414.

It is an arithmetic number, because the mean of its divisors is an integer number (99310950).

Almost surely, 2^661512535 is an apocalyptic number.

661512535 is a deficient number, since it is larger than the sum of its proper divisors (132975065).

661512535 is a wasteful number, since it uses less digits than its factorization.

661512535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112097.

The product of its digits is 27000, while the sum is 34.

The square root of 661512535 is about 25719.8859834176. The cubic root of 661512535 is about 871.3233636377.

It can be divided in two parts, 66151 and 2535, that added together give a palindrome (68686).

The spelling of 661512535 in words is "six hundred sixty-one million, five hundred twelve thousand, five hundred thirty-five".