1643549376 has 168 divisors, whose sum is σ = 5113513776. Its totient is φ = 464486400.

The previous prime is 1643549359. The next prime is 1643549377. The reversal of 1643549376 is 6739453461.

It is a tau number, because it is divible by the number of its divisors (168).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (1643549377) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 911676 + ... + 913476.

It is an arithmetic number, because the mean of its divisors is an integer number (30437582).

Almost surely, 2^1643549376 is an apocalyptic number.

1643549376 is a gapful number since it is divisible by the number (16) 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 1643549376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2556756888).

1643549376 is an abundant number, since it is smaller than the sum of its proper divisors (3469964400).

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

1643549376 is a wasteful number, since it uses less digits than its factorization.

1643549376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1927 (or 1910 counting only the distinct ones).

The product of its digits is 1632960, while the sum is 48.

The square root of 1643549376 is about 40540.7125739053. The cubic root of 1643549376 is about 1180.1238441310.

The spelling of 1643549376 in words is "one billion, six hundred forty-three million, five hundred forty-nine thousand, three hundred seventy-six".