75512470021 has 2 divisors, whose sum is σ = 75512470022. Its totient is φ = 75512470020.

The previous prime is 75512470009. The next prime is 75512470037. The reversal of 75512470021 is 12007421557.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60393062500 + 15119407521 = 245750^2 + 122961^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-75512470021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (75512470421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37756235010 + 37756235011.

It is an arithmetic number, because the mean of its divisors is an integer number (37756235011).

Almost surely, 2^75512470021 is an apocalyptic number.

It is an amenable number.

75512470021 is a deficient number, since it is larger than the sum of its proper divisors (1).

75512470021 is an equidigital number, since it uses as much as digits as its factorization.

75512470021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19600, while the sum is 34.

Adding to 75512470021 its reverse (12007421557), we get a palindrome (87519891578).

The spelling of 75512470021 in words is "seventy-five billion, five hundred twelve million, four hundred seventy thousand, twenty-one".