1156213440 has 168 divisors, whose sum is σ = 4124462160. Its totient is φ = 308302848.

The previous prime is 1156213423. The next prime is 1156213451. The reversal of 1156213440 is 443126511.

It is a happy number.

1156213440 is a `hidden beast` number, since 1 + 1 + 5 + 6 + 213 + 440 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 70326 + ... + 85194.

It is an arithmetic number, because the mean of its divisors is an integer number (24550370).

Almost surely, 2^1156213440 is an apocalyptic number.

1156213440 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 1156213440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2062231080).

1156213440 is an abundant number, since it is smaller than the sum of its proper divisors (2968248720).

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

1156213440 is an equidigital number, since it uses as much as digits as its factorization.

1156213440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14901 (or 14879 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 1156213440 is about 34003.1386786573. The cubic root of 1156213440 is about 1049.5730509081.

Adding to 1156213440 its reverse (443126511), we get a palindrome (1599339951).

The spelling of 1156213440 in words is "one billion, one hundred fifty-six million, two hundred thirteen thousand, four hundred forty".