1645613632 has 56 divisors (see below), whose sum is σ = 3591616896. Its totient is φ = 743336448.

The previous prime is 1645613621. The next prime is 1645613771. The reversal of 1645613632 is 2363165461.

It is a junction number, because it is equal to n+sod(n) for n = 1645613591 and 1645613600.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18063 + ... + 60145.

It is an arithmetic number, because the mean of its divisors is an integer number (64136016).

Almost surely, 2^1645613632 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 1645613632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1795808448).

1645613632 is an abundant number, since it is smaller than the sum of its proper divisors (1946003264).

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

1645613632 is a wasteful number, since it uses less digits than its factorization.

1645613632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42155 (or 42145 counting only the distinct ones).

The product of its digits is 77760, while the sum is 37.

The square root of 1645613632 is about 40566.1636342408. The cubic root of 1645613632 is about 1180.6177058891.

The spelling of 1645613632 in words is "one billion, six hundred forty-five million, six hundred thirteen thousand, six hundred thirty-two".