631785609 has 64 divisors (see below), whose sum is σ = 1176698880. Its totient is φ = 326099520.

The previous prime is 631785607. The next prime is 631785641. The reversal of 631785609 is 906587136.

It is a happy number.

631785609 is a `hidden beast` number, since 6 + 31 + 7 + 8 + 5 + 609 = 666.

It is not a de Polignac number, because 631785609 - 2¹ = 631785607 is a prime.

It is not an unprimeable number, because it can be changed into a prime (631785607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 112744 + ... + 118214.

It is an arithmetic number, because the mean of its divisors is an integer number (18385920).

Almost surely, 2^631785609 is an apocalyptic number.

It is an amenable number.

631785609 is a deficient number, since it is larger than the sum of its proper divisors (544913271).

631785609 is a wasteful number, since it uses less digits than its factorization.

631785609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5547 (or 5541 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The square root of 631785609 is about 25135.3458102330. The cubic root of 631785609 is about 858.0710367122.

The spelling of 631785609 in words is "six hundred thirty-one million, seven hundred eighty-five thousand, six hundred nine".