1645808181888 has 768 divisors, whose sum is σ = 5055947424000. Its totient is φ = 473404538880.

The previous prime is 1645808181887. The next prime is 1645808181889. The reversal of 1645808181888 is 8881818085461.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1645808181887) and next prime (1645808181889).

It is not an unprimeable number, because it can be changed into a prime (1645808181887) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 14564674120 + ... + 14564674232.

It is an arithmetic number, because the mean of its divisors is an integer number (6583264875).

Almost surely, 2^{1645808181888} 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 1645808181888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2527973712000).

1645808181888 is an abundant number, since it is smaller than the sum of its proper divisors (3410139242112).

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

1645808181888 is a wasteful number, since it uses less digits than its factorization.

1645808181888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365 (or 340 counting only the distinct ones).

The product of its (nonzero) digits is 31457280, while the sum is 66.

The spelling of 1645808181888 in words is "one trillion, six hundred forty-five billion, eight hundred eight million, one hundred eighty-one thousand, eight hundred eighty-eight".