55551389 has 2 divisors, whose sum is σ = 55551390. Its totient is φ = 55551388.

The previous prime is 55551361. The next prime is 55551401. The reversal of 55551389 is 98315555.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49815364 + 5736025 = 7058^2 + 2395^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55551389 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55551329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27775694 + 27775695.

It is an arithmetic number, because the mean of its divisors is an integer number (27775695).

Almost surely, 2^55551389 is an apocalyptic number.

It is an amenable number.

55551389 is a deficient number, since it is larger than the sum of its proper divisors (1).

55551389 is an equidigital number, since it uses as much as digits as its factorization.

55551389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 135000, while the sum is 41.

The square root of 55551389 is about 7453.2804187150. The cubic root of 55551389 is about 381.5618749150.

The spelling of 55551389 in words is "fifty-five million, five hundred fifty-one thousand, three hundred eighty-nine".