16550421389 has 2 divisors, whose sum is σ = 16550421390. Its totient is φ = 16550421388.

The previous prime is 16550421359. The next prime is 16550421401. The reversal of 16550421389 is 98312405561.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16516105225 + 34316164 = 128515^2 + 5858^2 .

It is a cyclic number.

It is not a de Polignac number, because 16550421389 - 2¹⁶ = 16550355853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16550421359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8275210694 + 8275210695.

It is an arithmetic number, because the mean of its divisors is an integer number (8275210695).

Almost surely, 2^16550421389 is an apocalyptic number.

It is an amenable number.

16550421389 is a deficient number, since it is larger than the sum of its proper divisors (1).

16550421389 is an equidigital number, since it uses as much as digits as its factorization.

16550421389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 259200, while the sum is 44.

The spelling of 16550421389 in words is "sixteen billion, five hundred fifty million, four hundred twenty-one thousand, three hundred eighty-nine".