655778 has 4 divisors (see below), whose sum is σ = 983670. Its totient is φ = 327888.

The previous prime is 655757. The next prime is 655807. The reversal of 655778 is 877556.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 418609 + 237169 = 647^2 + 487^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 163943 + ... + 163946.

2⁶⁵⁵⁷⁷⁸ is an apocalyptic number.

655778 is a deficient number, since it is larger than the sum of its proper divisors (327892).

655778 is a wasteful number, since it uses less digits than its factorization.

655778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327891.

The product of its digits is 58800, while the sum is 38.

The square root of 655778 is about 809.8012101744. The cubic root of 655778 is about 86.8798270354.

The spelling of 655778 in words is "six hundred fifty-five thousand, seven hundred seventy-eight".