991026973 has 4 divisors (see below), whose sum is σ = 992021980. Its totient is φ = 990032964.

The previous prime is 991026899. The next prime is 991026979. The reversal of 991026973 is 379620199.

The cubic root of 991026973 is 997.

It is a perfect power (a cube), and thus also a powerful number.

It can be written as a sum of positive squares in 2 ways, for example, as 699232249 + 291794724 = 26443^2 + 17082^2 .

It is not a de Polignac number, because 991026973 - 2¹⁷ = 990895901 is a prime.

It is a super-2 number, since 2×991026973² = 1964268922427085458, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991026979) 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, 993511 + ... + 994507.

It is an arithmetic number, because the mean of its divisors is an integer number (248005495).

Almost surely, 2^991026973 is an apocalyptic number.

It is an amenable number.

991026973 is a deficient number, since it is larger than the sum of its proper divisors (995007).

991026973 is an frugal number, since it uses more digits than its factorization.

991026973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2991 (or 997 counting only the distinct ones).

The product of its (nonzero) digits is 183708, while the sum is 46.

The square root of 991026973 is about 31480.5808872708.

The spelling of 991026973 in words is "nine hundred ninety-one million, twenty-six thousand, nine hundred seventy-three".