15764981 has 2 divisors, whose sum is σ = 15764982. Its totient is φ = 15764980.

The previous prime is 15764941. The next prime is 15764999. The reversal of 15764981 is 18946751.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14945956 + 819025 = 3866^2 + 905^2 .

It is an emirp because it is prime and its reverse (18946751) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15764981 is a prime.

It is a super-2 number, since 2×15764981² = 497069251860722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15764921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7882490 + 7882491.

It is an arithmetic number, because the mean of its divisors is an integer number (7882491).

Almost surely, 2^15764981 is an apocalyptic number.

It is an amenable number.

15764981 is a deficient number, since it is larger than the sum of its proper divisors (1).

15764981 is an equidigital number, since it uses as much as digits as its factorization.

15764981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 41.

The square root of 15764981 is about 3970.5139465817. The cubic root of 15764981 is about 250.7443469245.

The spelling of 15764981 in words is "fifteen million, seven hundred sixty-four thousand, nine hundred eighty-one".