609885540 has 144 divisors (see below), whose sum is σ = 2137000320. Its totient is φ = 139146240.

The previous prime is 609885539. The next prime is 609885547. The reversal of 609885540 is 45588906.

609885540 is a `hidden beast` number, since 6 + 0 + 98 + 8 + 554 + 0 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

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

It is not an unprimeable number, because it can be changed into a prime (609885547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 24601 + ... + 42719.

It is an arithmetic number, because the mean of its divisors is an integer number (14840280).

Almost surely, 2^609885540 is an apocalyptic number.

609885540 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 609885540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1068500160).

609885540 is an abundant number, since it is smaller than the sum of its proper divisors (1527114780).

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

609885540 is a wasteful number, since it uses less digits than its factorization.

609885540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18162 (or 18157 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 45.

The square root of 609885540 is about 24695.8607867796. The cubic root of 609885540 is about 848.0395603503.

The spelling of 609885540 in words is "six hundred nine million, eight hundred eighty-five thousand, five hundred forty".