158647981 has 2 divisors, whose sum is σ = 158647982. Its totient is φ = 158647980.

The previous prime is 158647963. The next prime is 158648003. The reversal of 158647981 is 189746851.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107453956 + 51194025 = 10366^2 + 7155^2 .

It is a cyclic number.

It is not a de Polignac number, because 158647981 - 2¹⁵ = 158615213 is a prime.

It is a super-3 number, since 3×158647981³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (158647481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79323990 + 79323991.

It is an arithmetic number, because the mean of its divisors is an integer number (79323991).

Almost surely, 2^158647981 is an apocalyptic number.

It is an amenable number.

158647981 is a deficient number, since it is larger than the sum of its proper divisors (1).

158647981 is an equidigital number, since it uses as much as digits as its factorization.

158647981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 483840, while the sum is 49.

The square root of 158647981 is about 12595.5540171919. The cubic root of 158647981 is about 541.3500524234.

The spelling of 158647981 in words is "one hundred fifty-eight million, six hundred forty-seven thousand, nine hundred eighty-one".