991494144 has 153 divisors (see below), whose sum is σ = 2935859329. Its totient is φ = 322437120.

The previous prime is 991494113. The next prime is 991494181. The reversal of 991494144 is 441494199.

The square root of 991494144 is 31488.

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

991494144 is a `hidden beast` number, since 99 + 149 + 414 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 47775744 + 943718400 = 6912^2 + 30720^2 .

It is a nude number because it is divisible by every one of its digits.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 991494144.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 24182764 + ... + 24182804.

Almost surely, 2^991494144 is an apocalyptic number.

991494144 is the 31488-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991494144

991494144 is an abundant number, since it is smaller than the sum of its proper divisors (1944365185).

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

991494144 is an frugal number, since it uses more digits than its factorization.

991494144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120 (or 46 counting only the distinct ones).

The product of its digits is 186624, while the sum is 45.

The cubic root of 991494144 is about 997.1566376196.

Multiplying 991494144 by its product of digits (186624), we get a square (185036603129856 = 13602816²).

Subtracting from 991494144 its reverse (441494199), we obtain a palindrome (549999945).

The spelling of 991494144 in words is "nine hundred ninety-one million, four hundred ninety-four thousand, one hundred forty-four".