15169981 has 2 divisors, whose sum is σ = 15169982. Its totient is φ = 15169980.

The previous prime is 15169919. The next prime is 15169991. The reversal of 15169981 is 18996151.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8357881 + 6812100 = 2891^2 + 2610^2 .

It is an emirp because it is prime and its reverse (18996151) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15169981 - 2¹⁹ = 14645693 is a prime.

It is a super-2 number, since 2×15169981² = 460256647080722, which contains 22 as substring.

It is equal to p₉₈₀₉₉₅ and since 15169981 and 980995 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15169901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7584990 + 7584991.

It is an arithmetic number, because the mean of its divisors is an integer number (7584991).

Almost surely, 2^15169981 is an apocalyptic number.

It is an amenable number.

15169981 is a deficient number, since it is larger than the sum of its proper divisors (1).

15169981 is an equidigital number, since it uses as much as digits as its factorization.

15169981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19440, while the sum is 40.

The square root of 15169981 is about 3894.8659797225. The cubic root of 15169981 is about 247.5492865149.

The spelling of 15169981 in words is "fifteen million, one hundred sixty-nine thousand, nine hundred eighty-one".