991737360 has 120 divisors (see below), whose sum is σ = 3445504920. Its totient is φ = 255338496.

The previous prime is 991737359. The next prime is 991737367. The reversal of 991737360 is 63737199.

It can be written as a sum of positive squares in 4 ways, for example, as 309900816 + 681836544 = 17604^2 + 26112^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (991737367) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2869 + ... + 44628.

It is an arithmetic number, because the mean of its divisors is an integer number (28712541).

Almost surely, 2^991737360 is an apocalyptic number.

991737360 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991737360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1722752460).

991737360 is an abundant number, since it is smaller than the sum of its proper divisors (2453767560).

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

991737360 is a wasteful number, since it uses less digits than its factorization.

991737360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47545 (or 47536 counting only the distinct ones).

The product of its (nonzero) digits is 214326, while the sum is 45.

The square root of 991737360 is about 31491.8618058698. The cubic root of 991737360 is about 997.2381659616.

The spelling of 991737360 in words is "nine hundred ninety-one million, seven hundred thirty-seven thousand, three hundred sixty".