55404521 has 2 divisors, whose sum is σ = 55404522. Its totient is φ = 55404520.

The previous prime is 55404499. The next prime is 55404527. The reversal of 55404521 is 12540455.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35868121 + 19536400 = 5989^2 + 4420^2 .

It is a cyclic number.

It is not a de Polignac number, because 55404521 - 2²² = 51210217 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (55404527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27702260 + 27702261.

It is an arithmetic number, because the mean of its divisors is an integer number (27702261).

Almost surely, 2^55404521 is an apocalyptic number.

It is an amenable number.

55404521 is a deficient number, since it is larger than the sum of its proper divisors (1).

55404521 is an equidigital number, since it uses as much as digits as its factorization.

55404521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4000, while the sum is 26.

The square root of 55404521 is about 7443.4213235581. The cubic root of 55404521 is about 381.2253175457.

Adding to 55404521 its reverse (12540455), we get a palindrome (67944976).

The spelling of 55404521 in words is "fifty-five million, four hundred four thousand, five hundred twenty-one".