55489813 has 2 divisors, whose sum is σ = 55489814. Its totient is φ = 55489812.

The previous prime is 55489801. The next prime is 55489817. The reversal of 55489813 is 31898455.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48972004 + 6517809 = 6998^2 + 2553^2 .

It is a cyclic number.

It is not a de Polignac number, because 55489813 - 2¹⁷ = 55358741 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 55489813.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55489817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27744906 + 27744907.

It is an arithmetic number, because the mean of its divisors is an integer number (27744907).

Almost surely, 2^55489813 is an apocalyptic number.

It is an amenable number.

55489813 is a deficient number, since it is larger than the sum of its proper divisors (1).

55489813 is an equidigital number, since it uses as much as digits as its factorization.

55489813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 172800, while the sum is 43.

The square root of 55489813 is about 7449.1484748258. The cubic root of 55489813 is about 381.4208418954.

The spelling of 55489813 in words is "fifty-five million, four hundred eighty-nine thousand, eight hundred thirteen".