19928123 has 2 divisors, whose sum is σ = 19928124. Its totient is φ = 19928122.

The previous prime is 19928119. The next prime is 19928149. The reversal of 19928123 is 32182991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19928123 - 2² = 19928119 is a prime.

It is not a weakly prime, because it can be changed into another prime (19928023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9964061 + 9964062.

It is an arithmetic number, because the mean of its divisors is an integer number (9964062).

Almost surely, 2^19928123 is an apocalyptic number.

19928123 is a deficient number, since it is larger than the sum of its proper divisors (1).

19928123 is an equidigital number, since it uses as much as digits as its factorization.

19928123 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7776, while the sum is 35.

The square root of 19928123 is about 4464.0926289673. The cubic root of 19928123 is about 271.1161976797.

The spelling of 19928123 in words is "nineteen million, nine hundred twenty-eight thousand, one hundred twenty-three".