1645844478 has 8 divisors (see below), whose sum is σ = 3291688968. Its totient is φ = 548614824.

The previous prime is 1645844461. The next prime is 1645844483. The reversal of 1645844478 is 8744485461.

It is a sphenic number, since it is the product of 3 distinct primes.

1645844478 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 1645844478.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 137153701 + ... + 137153712.

It is an arithmetic number, because the mean of its divisors is an integer number (411461121).

Almost surely, 2^1645844478 is an apocalyptic number.

1645844478 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1645844478 is a wasteful number, since it uses less digits than its factorization.

1645844478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274307418.

The product of its digits is 3440640, while the sum is 51.

The square root of 1645844478 is about 40569.0088367956. The cubic root of 1645844478 is about 1180.6729088291.

The spelling of 1645844478 in words is "one billion, six hundred forty-five million, eight hundred forty-four thousand, four hundred seventy-eight".