19498981 has 2 divisors, whose sum is σ = 19498982. Its totient is φ = 19498980.

The previous prime is 19498951. The next prime is 19499041. The reversal of 19498981 is 18989491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17986081 + 1512900 = 4241^2 + 1230^2 .

It is an emirp because it is prime and its reverse (18989491) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19498981 - 2¹⁹ = 18974693 is a prime.

It is a super-2 number, since 2×19498981² = 760420520076722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19498951) 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 as a sum of consecutive naturals, namely, 9749490 + 9749491.

It is an arithmetic number, because the mean of its divisors is an integer number (9749491).

Almost surely, 2^19498981 is an apocalyptic number.

It is an amenable number.

19498981 is a deficient number, since it is larger than the sum of its proper divisors (1).

19498981 is an equidigital number, since it uses as much as digits as its factorization.

19498981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 49.

The square root of 19498981 is about 4415.7650526268. The cubic root of 19498981 is about 269.1559420666.

The spelling of 19498981 in words is "nineteen million, four hundred ninety-eight thousand, nine hundred eighty-one".