991434634 has 4 divisors (see below), whose sum is σ = 1487151954. Its totient is φ = 495717316.

The previous prime is 991434601. The next prime is 991434641. The reversal of 991434634 is 436434199.

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

It can be written as a sum of positive squares in only one way, i.e., 547700409 + 443734225 = 23403^2 + 21065^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 247858657 + ... + 247858660.

Almost surely, 2^991434634 is an apocalyptic number.

991434634 is a deficient number, since it is larger than the sum of its proper divisors (495717320).

991434634 is a wasteful number, since it uses less digits than its factorization.

991434634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495717319.

The product of its digits is 279936, while the sum is 43.

The square root of 991434634 is about 31487.0550226597. The cubic root of 991434634 is about 997.1366872652.

The spelling of 991434634 in words is "nine hundred ninety-one million, four hundred thirty-four thousand, six hundred thirty-four".