1156821120 has 384 divisors, whose sum is σ = 4918717440. Its totient is φ = 243965952.

The previous prime is 1156821101. The next prime is 1156821143. The reversal of 1156821120 is 211286511.

It is a tau number, because it is divible by the number of its divisors (384).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 523057 + ... + 525263.

It is an arithmetic number, because the mean of its divisors is an integer number (12809160).

Almost surely, 2^1156821120 is an apocalyptic number.

1156821120 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 1156821120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2459358720).

1156821120 is an abundant number, since it is smaller than the sum of its proper divisors (3761896320).

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

1156821120 is a wasteful number, since it uses less digits than its factorization.

1156821120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2252 (or 2237 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 27.

The square root of 1156821120 is about 34012.0731505740. The cubic root of 1156821120 is about 1049.7568961001.

The spelling of 1156821120 in words is "one billion, one hundred fifty-six million, eight hundred twenty-one thousand, one hundred twenty".