71635599421 has 2 divisors, whose sum is σ = 71635599422. Its totient is φ = 71635599420.

The previous prime is 71635599403. The next prime is 71635599443. The reversal of 71635599421 is 12499553617.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 56577855321 + 15057744100 = 237861^2 + 122710^2 .

It is a cyclic number.

It is not a de Polignac number, because 71635599421 - 2²⁵ = 71602044989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71635599221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35817799710 + 35817799711.

It is an arithmetic number, because the mean of its divisors is an integer number (35817799711).

Almost surely, 2^71635599421 is an apocalyptic number.

It is an amenable number.

71635599421 is a deficient number, since it is larger than the sum of its proper divisors (1).

71635599421 is an equidigital number, since it uses as much as digits as its factorization.

71635599421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2041200, while the sum is 52.

The spelling of 71635599421 in words is "seventy-one billion, six hundred thirty-five million, five hundred ninety-nine thousand, four hundred twenty-one".