655219987 has 2 divisors, whose sum is σ = 655219988. Its totient is φ = 655219986.

The previous prime is 655219979. The next prime is 655220017. The reversal of 655219987 is 789912556.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 655219987 - 2³ = 655219979 is a prime.

It is not a weakly prime, because it can be changed into another prime (655219927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327609993 + 327609994.

It is an arithmetic number, because the mean of its divisors is an integer number (327609994).

Almost surely, 2^655219987 is an apocalyptic number.

655219987 is a deficient number, since it is larger than the sum of its proper divisors (1).

655219987 is an equidigital number, since it uses as much as digits as its factorization.

655219987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1360800, while the sum is 52.

The square root of 655219987 is about 25597.2652250196. The cubic root of 655219987 is about 868.5517751974.

The spelling of 655219987 in words is "six hundred fifty-five million, two hundred nineteen thousand, nine hundred eighty-seven".