167986981 has 2 divisors, whose sum is σ = 167986982. Its totient is φ = 167986980.

The previous prime is 167986969. The next prime is 167987033. The reversal of 167986981 is 189689761.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 162154756 + 5832225 = 12734^2 + 2415^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-167986981 is a prime.

It is a super-2 number, since 2×167986981² = 56439251570988722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (167986381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83993490 + 83993491.

It is an arithmetic number, because the mean of its divisors is an integer number (83993491).

Almost surely, 2^167986981 is an apocalyptic number.

It is an amenable number.

167986981 is a deficient number, since it is larger than the sum of its proper divisors (1).

167986981 is an equidigital number, since it uses as much as digits as its factorization.

167986981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1306368, while the sum is 55.

The square root of 167986981 is about 12960.9791682573. The cubic root of 167986981 is about 551.7705815613.

The spelling of 167986981 in words is "one hundred sixty-seven million, nine hundred eighty-six thousand, nine hundred eighty-one".