19836981 has 10 divisors (see below), whose sum is σ = 29633142. Its totient is φ = 13224600.

The previous prime is 19836967. The next prime is 19836983. The reversal of 19836981 is 18963891.

It can be written as a sum of positive squares in only one way, i.e., 13024881 + 6812100 = 3609^2 + 2610^2 .

It is not a de Polignac number, because 19836981 - 2⁷ = 19836853 is a prime.

It is a super-2 number, since 2×19836981² = 787011630388722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19836983) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 122370 + ... + 122531.

Almost surely, 2^19836981 is an apocalyptic number.

It is an amenable number.

19836981 is a deficient number, since it is larger than the sum of its proper divisors (9796161).

19836981 is an equidigital number, since it uses as much as digits as its factorization.

19836981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244913 (or 244904 counting only the distinct ones).

The product of its digits is 93312, while the sum is 45.

The square root of 19836981 is about 4453.8725846167. The cubic root of 19836981 is about 270.7022460111.

The spelling of 19836981 in words is "nineteen million, eight hundred thirty-six thousand, nine hundred eighty-one".