38720434101721 has 2 divisors, whose sum is σ = 38720434101722. Its totient is φ = 38720434101720.

The previous prime is 38720434101703. The next prime is 38720434101761. The reversal of 38720434101721 is 12710143402783.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38180597112025 + 539836989696 = 6179045^2 + 734736^2 .

It is a cyclic number.

It is not a de Polignac number, because 38720434101721 - 2³⁵ = 38686074363353 is a prime.

It is not a weakly prime, because it can be changed into another prime (38720434101761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19360217050860 + 19360217050861.

It is an arithmetic number, because the mean of its divisors is an integer number (19360217050861).

Almost surely, 2^{38720434101721} is an apocalyptic number.

It is an amenable number.

38720434101721 is a deficient number, since it is larger than the sum of its proper divisors (1).

38720434101721 is an equidigital number, since it uses as much as digits as its factorization.

38720434101721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 225792, while the sum is 43.

The spelling of 38720434101721 in words is "thirty-eight trillion, seven hundred twenty billion, four hundred thirty-four million, one hundred one thousand, seven hundred twenty-one".