19923161 has 2 divisors, whose sum is σ = 19923162. Its totient is φ = 19923160.

The previous prime is 19923157. The next prime is 19923193. The reversal of 19923161 is 16132991.

It is an a-pointer prime, because the next prime (19923193) can be obtained adding 19923161 to its sum of digits (32).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11256025 + 8667136 = 3355^2 + 2944^2 .

It is a cyclic number.

It is not a de Polignac number, because 19923161 - 2² = 19923157 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19923151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9961580 + 9961581.

It is an arithmetic number, because the mean of its divisors is an integer number (9961581).

Almost surely, 2^19923161 is an apocalyptic number.

It is an amenable number.

19923161 is a deficient number, since it is larger than the sum of its proper divisors (1).

19923161 is an equidigital number, since it uses as much as digits as its factorization.

19923161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2916, while the sum is 32.

The square root of 19923161 is about 4463.5368263295. The cubic root of 19923161 is about 271.0936936328.

The spelling of 19923161 in words is "nineteen million, nine hundred twenty-three thousand, one hundred sixty-one".