19818101 has 2 divisors, whose sum is σ = 19818102. Its totient is φ = 19818100.

The previous prime is 19818091. The next prime is 19818103. The reversal of 19818101 is 10181891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10824100 + 8994001 = 3290^2 + 2999^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19818101 is a prime.

Together with 19818103, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19818103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9909050 + 9909051.

It is an arithmetic number, because the mean of its divisors is an integer number (9909051).

Almost surely, 2^19818101 is an apocalyptic number.

It is an amenable number.

19818101 is a deficient number, since it is larger than the sum of its proper divisors (1).

19818101 is an equidigital number, since it uses as much as digits as its factorization.

19818101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 29.

The square root of 19818101 is about 4451.7525762333. The cubic root of 19818101 is about 270.6163377657.

Adding to 19818101 its reverse (10181891), we get a palindrome (29999992).

The spelling of 19818101 in words is "nineteen million, eight hundred eighteen thousand, one hundred one".