634669987 has 4 divisors (see below), whose sum is σ = 725337136. Its totient is φ = 544002840.

The previous prime is 634669949. The next prime is 634670009. The reversal of 634669987 is 789966436.

634669987 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 634669987 - 2²⁷ = 500452259 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (634669907) 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, 45333564 + ... + 45333577.

It is an arithmetic number, because the mean of its divisors is an integer number (181334284).

Almost surely, 2^634669987 is an apocalyptic number.

634669987 is a deficient number, since it is larger than the sum of its proper divisors (90667149).

634669987 is an equidigital number, since it uses as much as digits as its factorization.

634669987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90667148.

The product of its digits is 11757312, while the sum is 58.

The square root of 634669987 is about 25192.6574025052. The cubic root of 634669987 is about 859.3748778790.

The spelling of 634669987 in words is "six hundred thirty-four million, six hundred sixty-nine thousand, nine hundred eighty-seven".