1155438380 has 96 divisors (see below), whose sum is σ = 2554675200. Its totient is φ = 438600960.

The previous prime is 1155438367. The next prime is 1155438397. The reversal of 1155438380 is 838345511.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7754546 + ... + 7754694.

It is an arithmetic number, because the mean of its divisors is an integer number (26611200).

Almost surely, 2^1155438380 is an apocalyptic number.

1155438380 is a gapful number since it is divisible by the number (10) 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 1155438380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1277337600).

1155438380 is an abundant number, since it is smaller than the sum of its proper divisors (1399236820).

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

1155438380 is a wasteful number, since it uses less digits than its factorization.

1155438380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399 (or 397 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 38.

The square root of 1155438380 is about 33991.7398789765. The cubic root of 1155438380 is about 1049.3384737100.

The spelling of 1155438380 in words is "one billion, one hundred fifty-five million, four hundred thirty-eight thousand, three hundred eighty".