655619897 has 2 divisors, whose sum is σ = 655619898. Its totient is φ = 655619896.

The previous prime is 655619879. The next prime is 655619903. The reversal of 655619897 is 798916556.

Together with previous prime (655619879) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 570445456 + 85174441 = 23884^2 + 9229^2 .

It is a cyclic number.

It is not a de Polignac number, because 655619897 - 2⁸ = 655619641 is a prime.

It is not a weakly prime, because it can be changed into another prime (655619197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327809948 + 327809949.

It is an arithmetic number, because the mean of its divisors is an integer number (327809949).

Almost surely, 2^655619897 is an apocalyptic number.

It is an amenable number.

655619897 is a deficient number, since it is larger than the sum of its proper divisors (1).

655619897 is an equidigital number, since it uses as much as digits as its factorization.

655619897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4082400, while the sum is 56.

The square root of 655619897 is about 25605.0756101207. The cubic root of 655619897 is about 868.7284445629.

The spelling of 655619897 in words is "six hundred fifty-five million, six hundred nineteen thousand, eight hundred ninety-seven".