19957513 has 2 divisors, whose sum is σ = 19957514. Its totient is φ = 19957512.

The previous prime is 19957501. The next prime is 19957523. The reversal of 19957513 is 31575991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14722569 + 5234944 = 3837^2 + 2288^2 .

It is an emirp because it is prime and its reverse (31575991) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19957513 is a prime.

It is not a weakly prime, because it can be changed into another prime (19957523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9978756 + 9978757.

It is an arithmetic number, because the mean of its divisors is an integer number (9978757).

Almost surely, 2^19957513 is an apocalyptic number.

It is an amenable number.

19957513 is a deficient number, since it is larger than the sum of its proper divisors (1).

19957513 is an equidigital number, since it uses as much as digits as its factorization.

19957513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42525, while the sum is 40.

The square root of 19957513 is about 4467.3832385413. The cubic root of 19957513 is about 271.2494129543.

The spelling of 19957513 in words is "nineteen million, nine hundred fifty-seven thousand, five hundred thirteen".