1156121400 has 192 divisors, whose sum is σ = 4154734080. Its totient is φ = 260467200.

The previous prime is 1156121377. The next prime is 1156121413. The reversal of 1156121400 is 41216511.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

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, 296262 + ... + 300138.

It is an arithmetic number, because the mean of its divisors is an integer number (21639240).

Almost surely, 2^1156121400 is an apocalyptic number.

1156121400 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 1156121400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2077367040).

1156121400 is an abundant number, since it is smaller than the sum of its proper divisors (2998612680).

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

1156121400 is a wasteful number, since it uses less digits than its factorization.

1156121400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3974 (or 3965 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 1156121400 is about 34001.7852472484. The cubic root of 1156121400 is about 1049.5451998603.

Adding to 1156121400 its reverse (41216511), we get a palindrome (1197337911).

The spelling of 1156121400 in words is "one billion, one hundred fifty-six million, one hundred twenty-one thousand, four hundred".