1121861664 has 540 divisors, whose sum is σ = 4276457262. Its totient is φ = 287400960.

The previous prime is 1121861651. The next prime is 1121861729. The reversal of 1121861664 is 4661681211.

1121861664 is a `hidden beast` number, since 11 + 21 + 8 + 616 + 6 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 929762064 + 192099600 = 30492^2 + 13860^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

Its product of digits (13824) is a multiple of the sum of its prime divisors (96).

It is an unprimeable number.

It is a polite number, since it can be written in 89 ways as a sum of consecutive naturals, for example, 15367932 + ... + 15368004.

Almost surely, 2^1121861664 is an apocalyptic number.

1121861664 is a gapful number since it is divisible by the number (14) 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 1121861664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2138228631).

1121861664 is an abundant number, since it is smaller than the sum of its proper divisors (3154595598).

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

1121861664 is a wasteful number, since it uses less digits than its factorization.

1121861664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131 (or 96 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 1121861664 is about 33494.2034388042. The cubic root of 1121861664 is about 1039.0738994354.

The spelling of 1121861664 in words is "one billion, one hundred twenty-one million, eight hundred sixty-one thousand, six hundred sixty-four".