15680381 has 2 divisors, whose sum is σ = 15680382. Its totient is φ = 15680380.

The previous prime is 15680369. The next prime is 15680383. The reversal of 15680381 is 18308651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12013156 + 3667225 = 3466^2 + 1915^2 .

It is an emirp because it is prime and its reverse (18308651) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15680381 - 2¹⁸ = 15418237 is a prime.

It is a super-2 number, since 2×15680381² = 491748696610322, which contains 22 as substring.

Together with 15680383, 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 (15680383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7840190 + 7840191.

It is an arithmetic number, because the mean of its divisors is an integer number (7840191).

Almost surely, 2^15680381 is an apocalyptic number.

It is an amenable number.

15680381 is a deficient number, since it is larger than the sum of its proper divisors (1).

15680381 is an equidigital number, since it uses as much as digits as its factorization.

15680381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 15680381 is about 3959.8460828674. The cubic root of 15680381 is about 250.2950170561.

It can be divided in two parts, 15680 and 381, that added together give a palindrome (16061).

The spelling of 15680381 in words is "fifteen million, six hundred eighty thousand, three hundred eighty-one".