55616728397 has 2 divisors, whose sum is σ = 55616728398. Its totient is φ = 55616728396.

The previous prime is 55616728393. The next prime is 55616728439. The reversal of 55616728397 is 79382761655.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51357077641 + 4259650756 = 226621^2 + 65266^2 .

It is a cyclic number.

It is not a de Polignac number, because 55616728397 - 2² = 55616728393 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55616728393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27808364198 + 27808364199.

It is an arithmetic number, because the mean of its divisors is an integer number (27808364199).

Almost surely, 2^55616728397 is an apocalyptic number.

It is an amenable number.

55616728397 is a deficient number, since it is larger than the sum of its proper divisors (1).

55616728397 is an equidigital number, since it uses as much as digits as its factorization.

55616728397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19051200, while the sum is 59.

The spelling of 55616728397 in words is "fifty-five billion, six hundred sixteen million, seven hundred twenty-eight thousand, three hundred ninety-seven".