19952321 has 2 divisors, whose sum is σ = 19952322. Its totient is φ = 19952320.

The previous prime is 19952311. The next prime is 19952329. The reversal of 19952321 is 12325991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18879025 + 1073296 = 4345^2 + 1036^2 .

It is an emirp because it is prime and its reverse (12325991) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19952321 is a prime.

It is a super-2 number, since 2×19952321² = 796190226574082, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (19952329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9976160 + 9976161.

It is an arithmetic number, because the mean of its divisors is an integer number (9976161).

Almost surely, 2^19952321 is an apocalyptic number.

It is an amenable number.

19952321 is a deficient number, since it is larger than the sum of its proper divisors (1).

19952321 is an equidigital number, since it uses as much as digits as its factorization.

19952321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4860, while the sum is 32.

The square root of 19952321 is about 4466.8020999368. The cubic root of 19952321 is about 271.2258888293.

The spelling of 19952321 in words is "nineteen million, nine hundred fifty-two thousand, three hundred twenty-one".