1611861120 has 640 divisors, whose sum is σ = 6398092800. Its totient is φ = 384860160.

The previous prime is 1611861113. The next prime is 1611861157. The reversal of 1611861120 is 211681161.

1611861120 is a `hidden beast` number, since 16 + 1 + 18 + 611 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

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

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 27319651 + ... + 27319709.

It is an arithmetic number, because the mean of its divisors is an integer number (9997020).

Almost surely, 2^1611861120 is an apocalyptic number.

1611861120 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 1611861120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3199046400).

1611861120 is an abundant number, since it is smaller than the sum of its proper divisors (4786231680).

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

1611861120 is a wasteful number, since it uses less digits than its factorization.

1611861120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The square root of 1611861120 is about 40147.9902361251. The cubic root of 1611861120 is about 1172.4901598397.

It can be divided in two parts, 16 and 11861120, that added together give a square (11861136 = 3444²).

The spelling of 1611861120 in words is "one billion, six hundred eleven million, eight hundred sixty-one thousand, one hundred twenty".