655918409 has 8 divisors (see below), whose sum is σ = 666182400. Its totient is φ = 645668496.

The previous prime is 655918387. The next prime is 655918423. The reversal of 655918409 is 904819556.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 655918409 - 2¹² = 655914313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (655918469) 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, 128072 + ... + 133094.

It is an arithmetic number, because the mean of its divisors is an integer number (83272800).

Almost surely, 2^655918409 is an apocalyptic number.

It is an amenable number.

655918409 is a deficient number, since it is larger than the sum of its proper divisors (10263991).

655918409 is a wasteful number, since it uses less digits than its factorization.

655918409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7039.

The product of its (nonzero) digits is 388800, while the sum is 47.

The square root of 655918409 is about 25610.9041035259. The cubic root of 655918409 is about 868.8602722263.

The spelling of 655918409 in words is "six hundred fifty-five million, nine hundred eighteen thousand, four hundred nine".