991564703 has 4 divisors (see below), whose sum is σ = 991640448. Its totient is φ = 991488960.

The previous prime is 991564681. The next prime is 991564709. The reversal of 991564703 is 307465199.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-991564703 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991564709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12626 + ... + 46287.

It is an arithmetic number, because the mean of its divisors is an integer number (247910112).

Almost surely, 2^991564703 is an apocalyptic number.

991564703 is a deficient number, since it is larger than the sum of its proper divisors (75745).

991564703 is a wasteful number, since it uses less digits than its factorization.

991564703 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75744.

The product of its (nonzero) digits is 204120, while the sum is 44.

The square root of 991564703 is about 31489.1203910176. The cubic root of 991564703 is about 997.1802910477.

The spelling of 991564703 in words is "nine hundred ninety-one million, five hundred sixty-four thousand, seven hundred three".