2165945040 has 540 divisors, whose sum is σ = 8883437004. Its totient is φ = 471453696.

The previous prime is 2165944997. The next prime is 2165945051. The reversal of 2165945040 is 405495612.

2165945040 is a `hidden beast` number, since 2 + 1 + 65 + 94 + 504 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 345744 + 2165599296 = 588^2 + 46536^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 2165944986 and 2165945004.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 29670444 + ... + 29670516.

Almost surely, 2^2165945040 is an apocalyptic number.

2165945040 is a gapful number since it is divisible by the number (20) 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 2165945040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4441718502).

2165945040 is an abundant number, since it is smaller than the sum of its proper divisors (6717491964).

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

2165945040 is a wasteful number, since it uses less digits than its factorization.

2165945040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The square root of 2165945040 is about 46539.7146531863. The cubic root of 2165945040 is about 1293.8456721240.

The spelling of 2165945040 in words is "two billion, one hundred sixty-five million, nine hundred forty-five thousand, forty".