75721121701 has 2 divisors, whose sum is σ = 75721121702. Its totient is φ = 75721121700.

The previous prime is 75721121681. The next prime is 75721121767. The reversal of 75721121701 is 10712112757.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57784948225 + 17936173476 = 240385^2 + 133926^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-75721121701 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (75721124701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37860560850 + 37860560851.

It is an arithmetic number, because the mean of its divisors is an integer number (37860560851).

Almost surely, 2^75721121701 is an apocalyptic number.

It is an amenable number.

75721121701 is a deficient number, since it is larger than the sum of its proper divisors (1).

75721121701 is an equidigital number, since it uses as much as digits as its factorization.

75721121701 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6860, while the sum is 34.

The spelling of 75721121701 in words is "seventy-five billion, seven hundred twenty-one million, one hundred twenty-one thousand, seven hundred one".