1645866880 has 192 divisors, whose sum is σ = 4727479680. Its totient is φ = 545771520.

The previous prime is 1645866877. The next prime is 1645866889. The reversal of 1645866880 is 886685461.

1645866880 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645866889) 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, 971314 + ... + 973006.

It is an arithmetic number, because the mean of its divisors is an integer number (24622290).

Almost surely, 2^1645866880 is an apocalyptic number.

1645866880 is a gapful number since it is divisible by the number (10) 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 1645866880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2363739840).

1645866880 is an abundant number, since it is smaller than the sum of its proper divisors (3081612800).

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

1645866880 is a wasteful number, since it uses less digits than its factorization.

1645866880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1757 (or 1738 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 52.

The square root of 1645866880 is about 40569.2849333088. The cubic root of 1645866880 is about 1180.6782656160.

It can be divided in two parts, 16458 and 66880, that added together give a palindrome (83338).

The spelling of 1645866880 in words is "one billion, six hundred forty-five million, eight hundred sixty-six thousand, eight hundred eighty".