1645442964 has 96 divisors (see below), whose sum is σ = 4675399680. Its totient is φ = 496303200.

The previous prime is 1645442957. The next prime is 1645442969. The reversal of 1645442964 is 4692445461.

1645442964 is a `hidden beast` number, since 16 + 4 + 544 + 2 + 96 + 4 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645442969) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 261819 + ... + 268029.

It is an arithmetic number, because the mean of its divisors is an integer number (48702080).

Almost surely, 2^1645442964 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1645442964, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2337699840).

1645442964 is an abundant number, since it is smaller than the sum of its proper divisors (3029956716).

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

1645442964 is a wasteful number, since it uses less digits than its factorization.

1645442964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6458 (or 6450 counting only the distinct ones).

The product of its digits is 829440, while the sum is 45.

The square root of 1645442964 is about 40564.0600039000. The cubic root of 1645442964 is about 1180.5768901867.

The spelling of 1645442964 in words is "one billion, six hundred forty-five million, four hundred forty-two thousand, nine hundred sixty-four".