65605421880 has 224 divisors, whose sum is σ = 226030651200. Its totient is φ = 17122192128.

The previous prime is 65605421851. The next prime is 65605421887. The reversal of 65605421880 is 8812450656.

65605421880 is a `hidden beast` number, since 6 + 560 + 5 + 4 + 2 + 1 + 8 + 80 = 666.

65605421880 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65605421887) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 1346586 + ... + 1394454.

Almost surely, 2^65605421880 is an apocalyptic number.

65605421880 is a gapful number since it is divisible by the number (60) 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 65605421880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113015325600).

65605421880 is an abundant number, since it is smaller than the sum of its proper divisors (160425229320).

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

65605421880 is a wasteful number, since it uses less digits than its factorization.

65605421880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47945 (or 47926 counting only the distinct ones).

The product of its (nonzero) digits is 460800, while the sum is 45.

The spelling of 65605421880 in words is "sixty-five billion, six hundred five million, four hundred twenty-one thousand, eight hundred eighty".