655549891 has 2 divisors, whose sum is σ = 655549892. Its totient is φ = 655549890.

The previous prime is 655549883. The next prime is 655549897. The reversal of 655549891 is 198945556.

655549891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 655549891 - 2³ = 655549883 is a prime.

It is a super-2 number, since 2×655549891² = 859491319180223762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (655549897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327774945 + 327774946.

It is an arithmetic number, because the mean of its divisors is an integer number (327774946).

Almost surely, 2^655549891 is an apocalyptic number.

655549891 is a deficient number, since it is larger than the sum of its proper divisors (1).

655549891 is an equidigital number, since it uses as much as digits as its factorization.

655549891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1944000, while the sum is 52.

The square root of 655549891 is about 25603.7085399752. The cubic root of 655549891 is about 868.6975230038.

The spelling of 655549891 in words is "six hundred fifty-five million, five hundred forty-nine thousand, eight hundred ninety-one".