19955389 has 4 divisors (see below), whose sum is σ = 19984960. Its totient is φ = 19925820.

The previous prime is 19955387. The next prime is 19955407. The reversal of 19955389 is 98355991.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 98355991 = 113 ⋅870407.

It is a cyclic number.

It is not a de Polignac number, because 19955389 - 2¹ = 19955387 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19955381) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13749 + ... + 15130.

It is an arithmetic number, because the mean of its divisors is an integer number (4996240).

Almost surely, 2^19955389 is an apocalyptic number.

It is an amenable number.

19955389 is a deficient number, since it is larger than the sum of its proper divisors (29571).

19955389 is an equidigital number, since it uses as much as digits as its factorization.

19955389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29570.

The product of its digits is 437400, while the sum is 49.

The square root of 19955389 is about 4467.1455091591. The cubic root of 19955389 is about 271.2397899418.

The spelling of 19955389 in words is "nineteen million, nine hundred fifty-five thousand, three hundred eighty-nine".