19120021 has 2 divisors, whose sum is σ = 19120022. Its totient is φ = 19120020.

The previous prime is 19120001. The next prime is 19120033. The reversal of 19120021 is 12002191.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15563025 + 3556996 = 3945^2 + 1886^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19120021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 19119977 and 19120004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19120001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9560010 + 9560011.

It is an arithmetic number, because the mean of its divisors is an integer number (9560011).

Almost surely, 2^19120021 is an apocalyptic number.

It is an amenable number.

19120021 is a deficient number, since it is larger than the sum of its proper divisors (1).

19120021 is an equidigital number, since it uses as much as digits as its factorization.

19120021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 19120021 is about 4372.6446231085. The cubic root of 19120021 is about 267.4008529993.

The spelling of 19120021 in words is "nineteen million, one hundred twenty thousand, twenty-one".