15005981 has 2 divisors, whose sum is σ = 15005982. Its totient is φ = 15005980.

The previous prime is 15005957. The next prime is 15005983. The reversal of 15005981 is 18950051.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14945956 + 60025 = 3866^2 + 245^2 .

It is a cyclic number.

It is not a de Polignac number, because 15005981 - 2¹⁸ = 14743837 is a prime.

It is a super-2 number, since 2×15005981² = 450358931544722, which contains 22 as substring.

Together with 15005983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15005983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7502990 + 7502991.

It is an arithmetic number, because the mean of its divisors is an integer number (7502991).

Almost surely, 2^15005981 is an apocalyptic number.

It is an amenable number.

15005981 is a deficient number, since it is larger than the sum of its proper divisors (1).

15005981 is an equidigital number, since it uses as much as digits as its factorization.

15005981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1800, while the sum is 29.

The square root of 15005981 is about 3873.7554130327. The cubic root of 15005981 is about 246.6539817761.

The spelling of 15005981 in words is "fifteen million, five thousand, nine hundred eighty-one".