991042925 has 12 divisors (see below), whose sum is σ = 1230156756. Its totient is φ = 792019200.

The previous prime is 991042879. The next prime is 991042961. The reversal of 991042925 is 529240199.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 34316164 + 956726761 = 5858^2 + 30931^2 .

It is not a de Polignac number, because 991042925 - 2¹⁰ = 991041901 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5045 + ... + 44805.

It is an arithmetic number, because the mean of its divisors is an integer number (102513063).

Almost surely, 2^991042925 is an apocalyptic number.

It is an amenable number.

991042925 is a deficient number, since it is larger than the sum of its proper divisors (239113831).

991042925 is a wasteful number, since it uses less digits than its factorization.

991042925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40768 (or 40763 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 41.

The square root of 991042925 is about 31480.8342487933. The cubic root of 991042925 is about 997.0053493528.

The spelling of 991042925 in words is "nine hundred ninety-one million, forty-two thousand, nine hundred twenty-five".