19768121 has 4 divisors (see below), whose sum is σ = 19780992. Its totient is φ = 19755252.

The previous prime is 19768117. The next prime is 19768129. The reversal of 19768121 is 12186791.

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: 12186791 = 401 ⋅30391.

It is a cyclic number.

It is not a de Polignac number, because 19768121 - 2² = 19768117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19768129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3761 + ... + 7326.

It is an arithmetic number, because the mean of its divisors is an integer number (4945248).

Almost surely, 2^19768121 is an apocalyptic number.

It is an amenable number.

19768121 is a deficient number, since it is larger than the sum of its proper divisors (12871).

19768121 is a wasteful number, since it uses less digits than its factorization.

19768121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12870.

The product of its digits is 6048, while the sum is 35.

The square root of 19768121 is about 4446.1355130045. The cubic root of 19768121 is about 270.3886538150.

The spelling of 19768121 in words is "nineteen million, seven hundred sixty-eight thousand, one hundred twenty-one".