1121639400 has 504 divisors, whose sum is σ = 4577254470. Its totient is φ = 254741760.

The previous prime is 1121639381. The next prime is 1121639401. The reversal of 1121639400 is 49361211.

1121639400 is a `hidden beast` number, since 1 + 1 + 21 + 639 + 4 + 0 + 0 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 720278244 + 401361156 = 26838^2 + 20034^2 .

It is a tau number, because it is divible by the number of its divisors (504).

It is a super-3 number, since 3×1121639400³ (a number of 28 digits) contains 333 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (1121639401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 125 ways as a sum of consecutive naturals, for example, 7144122 + ... + 7144278.

Almost surely, 2^1121639400 is an apocalyptic number.

1121639400 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 1121639400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2288627235).

1121639400 is an abundant number, since it is smaller than the sum of its proper divisors (3455615070).

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

1121639400 is a wasteful number, since it uses less digits than its factorization.

1121639400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205 (or 174 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 1121639400 is about 33490.8853272051. The cubic root of 1121639400 is about 1039.0052742260.

The spelling of 1121639400 in words is "one billion, one hundred twenty-one million, six hundred thirty-nine thousand, four hundred".