101717620721 has 2 divisors, whose sum is σ = 101717620722. Its totient is φ = 101717620720.

The previous prime is 101717620699. The next prime is 101717620747. The reversal of 101717620721 is 127026717101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84625719025 + 17091901696 = 290905^2 + 130736^2 .

It is an emirp because it is prime and its reverse (127026717101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 101717620721 - 2²² = 101713426417 is a prime.

It is not a weakly prime, because it can be changed into another prime (101717620751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50858810360 + 50858810361.

It is an arithmetic number, because the mean of its divisors is an integer number (50858810361).

Almost surely, 2^101717620721 is an apocalyptic number.

It is an amenable number.

101717620721 is a deficient number, since it is larger than the sum of its proper divisors (1).

101717620721 is an equidigital number, since it uses as much as digits as its factorization.

101717620721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8232, while the sum is 35.

The spelling of 101717620721 in words is "one hundred one billion, seven hundred seventeen million, six hundred twenty thousand, seven hundred twenty-one".