1645204992 has 80 divisors (see below), whose sum is σ = 4425907200. Its totient is φ = 543025152.

The previous prime is 1645204969. The next prime is 1645205063. The reversal of 1645204992 is 2994025461.

It is a congruent number.

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, 153009 + ... + 163407.

It is an arithmetic number, because the mean of its divisors is an integer number (55323840).

Almost surely, 2^1645204992 is an apocalyptic number.

1645204992 is a gapful number since it is divisible by the number (12) 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 1645204992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2212953600).

1645204992 is an abundant number, since it is smaller than the sum of its proper divisors (2780702208).

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

1645204992 is a wasteful number, since it uses less digits than its factorization.

1645204992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10523 (or 10507 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 42.

The square root of 1645204992 is about 40561.1266115723. The cubic root of 1645204992 is about 1180.5199738437.

The spelling of 1645204992 in words is "one billion, six hundred forty-five million, two hundred four thousand, nine hundred ninety-two".