99991552 has 60 divisors (see below), whose sum is σ = 212330160. Its totient is φ = 46923776.

The previous prime is 99991519. The next prime is 99991559. The reversal of 99991552 is 25519999.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 99991496 and 99991505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99991559) 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, 278349 + ... + 278707.

It is an arithmetic number, because the mean of its divisors is an integer number (3538836).

Almost surely, 2^99991552 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 99991552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106165080).

99991552 is an abundant number, since it is smaller than the sum of its proper divisors (112338608).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

99991552 is an equidigital number, since it uses as much as digits as its factorization.

99991552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404 (or 378 counting only the distinct ones).

The product of its digits is 328050, while the sum is 49.

The square root of 99991552 is about 9999.5775910785. The cubic root of 99991552 is about 464.1458122790.

The spelling of 99991552 in words is "ninety-nine million, nine hundred ninety-one thousand, five hundred fifty-two".