655540240 has 40 divisors (see below), whose sum is σ = 1527402240. Its totient is φ = 261653376.

The previous prime is 655540163. The next prime is 655540243. The reversal of 655540240 is 42045556.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (655540243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29767 + ... + 46873.

It is an arithmetic number, because the mean of its divisors is an integer number (38185056).

Almost surely, 2^655540240 is an apocalyptic number.

It is an amenable number.

655540240 is an abundant number, since it is smaller than the sum of its proper divisors (871862000).

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

655540240 is a wasteful number, since it uses less digits than its factorization.

655540240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17599 (or 17593 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 31.

The square root of 655540240 is about 25603.5200704903. The cubic root of 655540240 is about 868.6932599970.

Adding to 655540240 its reverse (42045556), we get a palindrome (697585796).

The spelling of 655540240 in words is "six hundred fifty-five million, five hundred forty thousand, two hundred forty".