1643561088 has 256 divisors, whose sum is σ = 5052378240. Its totient is φ = 468910080.

The previous prime is 1643561081. The next prime is 1643561107. The reversal of 1643561088 is 8801653461.

It is not an unprimeable number, because it can be changed into a prime (1643561081) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9080358 + ... + 9080538.

Almost surely, 2^1643561088 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 1643561088, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2526189120).

1643561088 is an abundant number, since it is smaller than the sum of its proper divisors (3408817152).

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

1643561088 is a wasteful number, since it uses less digits than its factorization.

1643561088 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335 (or 323 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 42.

The square root of 1643561088 is about 40540.8570210350. The cubic root of 1643561088 is about 1180.1266473279.

The spelling of 1643561088 in words is "one billion, six hundred forty-three million, five hundred sixty-one thousand, eighty-eight".