1155721140 has 72 divisors (see below), whose sum is σ = 4006504320. Its totient is φ = 264164544.

The previous prime is 1155721139. The next prime is 1155721153. The reversal of 1155721140 is 411275511.

1155721140 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 457360 + ... + 459879.

Almost surely, 2^1155721140 is an apocalyptic number.

1155721140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1155721140 is an abundant number, since it is smaller than the sum of its proper divisors (2850783180).

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

1155721140 is a wasteful number, since it uses less digits than its factorization.

1155721140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 917261 (or 917256 counting only the distinct ones).

The product of its (nonzero) digits is 1400, while the sum is 27.

The square root of 1155721140 is about 33995.8988703049. The cubic root of 1155721140 is about 1049.4240651044.

Adding to 1155721140 its reverse (411275511), we get a palindrome (1566996651).

The spelling of 1155721140 in words is "one billion, one hundred fifty-five million, seven hundred twenty-one thousand, one hundred forty".