1645432992 has 288 divisors, whose sum is σ = 5805281664. Its totient is φ = 431308800.

The previous prime is 1645432981. The next prime is 1645432993. The reversal of 1645432992 is 2992345461.

1645432992 is a `hidden beast` number, since 16 + 4 + 543 + 2 + 9 + 92 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is not an unprimeable number, because it can be changed into a prime (1645432993) 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, 1404567 + ... + 1405737.

It is an arithmetic number, because the mean of its divisors is an integer number (20157228).

Almost surely, 2^1645432992 is an apocalyptic number.

1645432992 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 1645432992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2902640832).

1645432992 is an abundant number, since it is smaller than the sum of its proper divisors (4159848672).

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

1645432992 is a wasteful number, since it uses less digits than its factorization.

1645432992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1252 (or 1241 counting only the distinct ones).

The product of its digits is 466560, while the sum is 45.

The square root of 1645432992 is about 40563.9370870235. The cubic root of 1645432992 is about 1180.5745052693.

The spelling of 1645432992 in words is "one billion, six hundred forty-five million, four hundred thirty-two thousand, nine hundred ninety-two".