635981649 has 8 divisors (see below), whose sum is σ = 853591872. Its totient is φ = 421179600.

The previous prime is 635981639. The next prime is 635981651. The reversal of 635981649 is 946189536.

635981649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 635981649 - 2²⁰ = 634933073 is a prime.

It is not an unprimeable number, because it can be changed into a prime (635981639) 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, 701514 + ... + 702419.

It is an arithmetic number, because the mean of its divisors is an integer number (106698984).

Almost surely, 2^635981649 is an apocalyptic number.

It is an amenable number.

635981649 is a deficient number, since it is larger than the sum of its proper divisors (217610223).

635981649 is a wasteful number, since it uses less digits than its factorization.

635981649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1404087.

The product of its digits is 1399680, while the sum is 51.

The square root of 635981649 is about 25218.6765909712. The cubic root of 635981649 is about 859.9664891395.

The spelling of 635981649 in words is "six hundred thirty-five million, nine hundred eighty-one thousand, six hundred forty-nine".