19954981 has 2 divisors, whose sum is σ = 19954982. Its totient is φ = 19954980.

The previous prime is 19954969. The next prime is 19955029. The reversal of 19954981 is 18945991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19061956 + 893025 = 4366^2 + 945^2 .

It is a cyclic number.

It is not a de Polignac number, because 19954981 - 2⁷ = 19954853 is a prime.

It is a super-2 number, since 2×19954981² = 796402533420722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19954681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9977490 + 9977491.

It is an arithmetic number, because the mean of its divisors is an integer number (9977491).

Almost surely, 2^19954981 is an apocalyptic number.

It is an amenable number.

19954981 is a deficient number, since it is larger than the sum of its proper divisors (1).

19954981 is an equidigital number, since it uses as much as digits as its factorization.

19954981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 116640, while the sum is 46.

The square root of 19954981 is about 4467.0998421795. The cubic root of 19954981 is about 271.2379413753.

The spelling of 19954981 in words is "nineteen million, nine hundred fifty-four thousand, nine hundred eighty-one".