1161997056 has 576 divisors, whose sum is σ = 4238438400. Its totient is φ = 309657600.

The previous prime is 1161997051. The next prime is 1161997091. The reversal of 1161997056 is 6507991611.

It is a tau number, because it is divible by the number of its divisors (576).

It is not an unprimeable number, because it can be changed into a prime (1161997051) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 37483761 + ... + 37483791.

It is an arithmetic number, because the mean of its divisors is an integer number (7358400).

Almost surely, 2^1161997056 is an apocalyptic number.

1161997056 is a gapful number since it is divisible by the number (16) 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 1161997056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2119219200).

1161997056 is an abundant number, since it is smaller than the sum of its proper divisors (3076441344).

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

1161997056 is a wasteful number, since it uses less digits than its factorization.

1161997056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113 (or 93 counting only the distinct ones).

The product of its (nonzero) digits is 102060, while the sum is 45.

The square root of 1161997056 is about 34088.0779158931. The cubic root of 1161997056 is about 1051.3202005958.

The spelling of 1161997056 in words is "one billion, one hundred sixty-one million, nine hundred ninety-seven thousand, fifty-six".