55621697 has 2 divisors, whose sum is σ = 55621698. Its totient is φ = 55621696.

The previous prime is 55621679. The next prime is 55621711. The reversal of 55621697 is 79612655.

Together with previous prime (55621679) 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., 51394561 + 4227136 = 7169^2 + 2056^2 .

It is a cyclic number.

It is not a de Polignac number, because 55621697 - 2⁸ = 55621441 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (55621627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27810848 + 27810849.

It is an arithmetic number, because the mean of its divisors is an integer number (27810849).

Almost surely, 2^55621697 is an apocalyptic number.

It is an amenable number.

55621697 is a deficient number, since it is larger than the sum of its proper divisors (1).

55621697 is an equidigital number, since it uses as much as digits as its factorization.

55621697 is an evil number, because the sum of its binary digits is even.

The product of its digits is 113400, while the sum is 41.

The square root of 55621697 is about 7457.9955081778. The cubic root of 55621697 is about 381.7227802379.

The spelling of 55621697 in words is "fifty-five million, six hundred twenty-one thousand, six hundred ninety-seven".