661335047 has 4 divisors (see below), whose sum is σ = 662634840. Its totient is φ = 660035256.

The previous prime is 661335041. The next prime is 661335049. The reversal of 661335047 is 740533166.

661335047 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 661335047 - 2⁶ = 661334983 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 661334998 and 661335016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661335041) 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, 649133 + ... + 650150.

It is an arithmetic number, because the mean of its divisors is an integer number (165658710).

Almost surely, 2^661335047 is an apocalyptic number.

661335047 is a deficient number, since it is larger than the sum of its proper divisors (1299793).

661335047 is a wasteful number, since it uses less digits than its factorization.

661335047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1299792.

The product of its (nonzero) digits is 45360, while the sum is 35.

The square root of 661335047 is about 25716.4353478471. The cubic root of 661335047 is about 871.2454294761.

The spelling of 661335047 in words is "six hundred sixty-one million, three hundred thirty-five thousand, forty-seven".