55021789 has 2 divisors, whose sum is σ = 55021790. Its totient is φ = 55021788.

The previous prime is 55021763. The next prime is 55021829. The reversal of 55021789 is 98712055.

55021789 = T₆₀₅₅ + T₆₀₅₆ + T₆₀₅₇.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37027225 + 17994564 = 6085^2 + 4242^2 .

It is a cyclic number.

It is not a de Polignac number, because 55021789 - 2⁹ = 55021277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55021189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27510894 + 27510895.

It is an arithmetic number, because the mean of its divisors is an integer number (27510895).

Almost surely, 2^55021789 is an apocalyptic number.

55021789 is the 6057-th centered triangular number.

It is an amenable number.

55021789 is a deficient number, since it is larger than the sum of its proper divisors (1).

55021789 is an equidigital number, since it uses as much as digits as its factorization.

55021789 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25200, while the sum is 37.

The square root of 55021789 is about 7417.6673557123. The cubic root of 55021789 is about 380.3454591617.

The spelling of 55021789 in words is "fifty-five million, twenty-one thousand, seven hundred eighty-nine".