199672981 has 2 divisors, whose sum is σ = 199672982. Its totient is φ = 199672980.

The previous prime is 199672969. The next prime is 199672999. The reversal of 199672981 is 189276991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 135512881 + 64160100 = 11641^2 + 8010^2 .

It is an emirp because it is prime and its reverse (189276991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199672981 - 2¹⁵ = 199640213 is a prime.

It is a super-2 number, since 2×199672981² = 79738598682852722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199672901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99836490 + 99836491.

It is an arithmetic number, because the mean of its divisors is an integer number (99836491).

Almost surely, 2^199672981 is an apocalyptic number.

It is an amenable number.

199672981 is a deficient number, since it is larger than the sum of its proper divisors (1).

199672981 is an equidigital number, since it uses as much as digits as its factorization.

199672981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 489888, while the sum is 52.

The square root of 199672981 is about 14130.5690260513. The cubic root of 199672981 is about 584.4846373109.

The spelling of 199672981 in words is "one hundred ninety-nine million, six hundred seventy-two thousand, nine hundred eighty-one".