1155438720 has 96 divisors (see below), whose sum is σ = 3989894220. Its totient is φ = 308115456.

The previous prime is 1155438617. The next prime is 1155438721. The reversal of 1155438720 is 278345511.

1155438720 is a `hidden beast` number, since 1 + 1 + 554 + 3 + 87 + 20 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1095345216 + 60093504 = 33096^2 + 7752^2 .

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1155438721) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 94539 + ... + 106058.

Almost surely, 2^1155438720 is an apocalyptic number.

1155438720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1155438720 is an abundant number, since it is smaller than the sum of its proper divisors (2834455500).

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

1155438720 is a wasteful number, since it uses less digits than its factorization.

1155438720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200622 (or 200607 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The square root of 1155438720 is about 33991.7448801911. The cubic root of 1155438720 is about 1049.3385766363.

The spelling of 1155438720 in words is "one billion, one hundred fifty-five million, four hundred thirty-eight thousand, seven hundred twenty".