661280042 has 8 divisors (see below), whose sum is σ = 1050268356. Its totient is φ = 311190592.

The previous prime is 661280041. The next prime is 661280089. The reversal of 661280042 is 240082166.

661280042 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 656435641 + 4844401 = 25621^2 + 2201^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 661279987 and 661280014.

It is not an unprimeable number, because it can be changed into a prime (661280041) 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, 9724673 + ... + 9724740.

Almost surely, 2^661280042 is an apocalyptic number.

661280042 is a deficient number, since it is larger than the sum of its proper divisors (388988314).

661280042 is a wasteful number, since it uses less digits than its factorization.

661280042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19449432.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 661280042 is about 25715.3658733451. The cubic root of 661280042 is about 871.2212742042.

The spelling of 661280042 in words is "six hundred sixty-one million, two hundred eighty thousand, forty-two".