19638713537 has 2 divisors, whose sum is σ = 19638713538. Its totient is φ = 19638713536.

The previous prime is 19638713467. The next prime is 19638713539. The reversal of 19638713537 is 73531783691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19615683136 + 23030401 = 140056^2 + 4799^2 .

It is a cyclic number.

It is not a de Polignac number, because 19638713537 - 2²⁶ = 19571604673 is a prime.

Together with 19638713539, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19638713539) 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, 9819356768 + 9819356769.

It is an arithmetic number, because the mean of its divisors is an integer number (9819356769).

Almost surely, 2^19638713537 is an apocalyptic number.

It is an amenable number.

19638713537 is a deficient number, since it is larger than the sum of its proper divisors (1).

19638713537 is an equidigital number, since it uses as much as digits as its factorization.

19638713537 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2857680, while the sum is 53.

The spelling of 19638713537 in words is "nineteen billion, six hundred thirty-eight million, seven hundred thirteen thousand, five hundred thirty-seven".