661409435 has 8 divisors (see below), whose sum is σ = 793841856. Its totient is φ = 529027200.

The previous prime is 661409383. The next prime is 661409471. The reversal of 661409435 is 534904166.

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

It is a de Polignac number, because none of the positive numbers 2^k-661409435 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28910 + ... + 46460.

It is an arithmetic number, because the mean of its divisors is an integer number (99230232).

Almost surely, 2^661409435 is an apocalyptic number.

661409435 is a deficient number, since it is larger than the sum of its proper divisors (132432421).

661409435 is a wasteful number, since it uses less digits than its factorization.

661409435 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25093.

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 661409435 is about 25717.8816196047. The cubic root of 661409435 is about 871.2780946007.

The spelling of 661409435 in words is "six hundred sixty-one million, four hundred nine thousand, four hundred thirty-five".