1645645122 has 96 divisors (see below), whose sum is σ = 3998502144. Its totient is φ = 484876800.

The previous prime is 1645645121. The next prime is 1645645139. The reversal of 1645645122 is 2215465461.

1645645122 is a `hidden beast` number, since 1 + 6 + 4 + 5 + 645 + 1 + 2 + 2 = 666.

It is not an unprimeable number, because it can be changed into a prime (1645645121) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1683898 + ... + 1684874.

It is an arithmetic number, because the mean of its divisors is an integer number (41651064).

Almost surely, 2^1645645122 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1645645122, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1999251072).

1645645122 is an abundant number, since it is smaller than the sum of its proper divisors (2352857022).

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

1645645122 is a wasteful number, since it uses less digits than its factorization.

1645645122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1224 (or 1221 counting only the distinct ones).

The product of its digits is 57600, while the sum is 36.

The square root of 1645645122 is about 40566.5517637376. The cubic root of 1645645122 is about 1180.6252364973.

The spelling of 1645645122 in words is "one billion, six hundred forty-five million, six hundred forty-five thousand, one hundred twenty-two".