991572469 has 8 divisors (see below), whose sum is σ = 1000840320. Its totient is φ = 982346400.

The previous prime is 991572457. The next prime is 991572473. The reversal of 991572469 is 964275199.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 991572469 - 2⁷ = 991572341 is a prime.

It is a super-3 number, since 3×991572469³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991572499) 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 7 ways as a sum of consecutive naturals, for example, 38289 + ... + 58729.

It is an arithmetic number, because the mean of its divisors is an integer number (125105040).

Almost surely, 2^991572469 is an apocalyptic number.

It is an amenable number.

991572469 is a deficient number, since it is larger than the sum of its proper divisors (9267851).

991572469 is a wasteful number, since it uses less digits than its factorization.

991572469 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20891.

The product of its digits is 1224720, while the sum is 52.

The square root of 991572469 is about 31489.2437032076. The cubic root of 991572469 is about 997.1828943681.

The spelling of 991572469 in words is "nine hundred ninety-one million, five hundred seventy-two thousand, four hundred sixty-nine".