555005981 has 2 divisors, whose sum is σ = 555005982. Its totient is φ = 555005980.

The previous prime is 555005951. The next prime is 555006013. The reversal of 555005981 is 189500555.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 436392100 + 118613881 = 20890^2 + 10891^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-555005981 is a prime.

It is a super-2 number, since 2×555005981² = 616063277891544722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (555005951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 277502990 + 277502991.

It is an arithmetic number, because the mean of its divisors is an integer number (277502991).

Almost surely, 2^555005981 is an apocalyptic number.

It is an amenable number.

555005981 is a deficient number, since it is larger than the sum of its proper divisors (1).

555005981 is an equidigital number, since it uses as much as digits as its factorization.

555005981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45000, while the sum is 38.

The square root of 555005981 is about 23558.5649180930. The cubic root of 555005981 is about 821.7995285283.

The spelling of 555005981 in words is "five hundred fifty-five million, five thousand, nine hundred eighty-one".