991973529 has 12 divisors (see below), whose sum is σ = 1434212416. Its totient is φ = 660687192.

The previous prime is 991973513. The next prime is 991973531. The reversal of 991973529 is 925379199.

It is not a de Polignac number, because 991973529 - 2⁴ = 991973513 is a prime.

It is a super-2 number, since 2×991973529² = 1968022964473427682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (991971529) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 42277 + ... + 61410.

Almost surely, 2^991973529 is an apocalyptic number.

It is an amenable number.

991973529 is a deficient number, since it is larger than the sum of its proper divisors (442238887).

991973529 is a wasteful number, since it uses less digits than its factorization.

991973529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104756 (or 104753 counting only the distinct ones).

The product of its digits is 1377810, while the sum is 54.

The square root of 991973529 is about 31495.6112656986. The cubic root of 991973529 is about 997.3173193266.

The spelling of 991973529 in words is "nine hundred ninety-one million, nine hundred seventy-three thousand, five hundred twenty-nine".