55011989 has 2 divisors, whose sum is σ = 55011990. Its totient is φ = 55011988.

The previous prime is 55011967. The next prime is 55012003. The reversal of 55011989 is 98911055.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55011889 + 100 = 7417^2 + 10^2 .

It is a cyclic number.

It is not a de Polignac number, because 55011989 - 2¹² = 55007893 is a prime.

It is a super-2 number, since 2×55011989² = 6052637867472242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55011959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27505994 + 27505995.

It is an arithmetic number, because the mean of its divisors is an integer number (27505995).

Almost surely, 2^55011989 is an apocalyptic number.

It is an amenable number.

55011989 is a deficient number, since it is larger than the sum of its proper divisors (1).

55011989 is an equidigital number, since it uses as much as digits as its factorization.

55011989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16200, while the sum is 38.

The square root of 55011989 is about 7417.0067412670. The cubic root of 55011989 is about 380.3228765517.

The spelling of 55011989 in words is "fifty-five million, eleven thousand, nine hundred eighty-nine".