71958521 has 2 divisors, whose sum is σ = 71958522. Its totient is φ = 71958520.

The previous prime is 71958517. The next prime is 71958563. The reversal of 71958521 is 12585917.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71639296 + 319225 = 8464^2 + 565^2 .

It is a cyclic number.

It is not a de Polignac number, because 71958521 - 2² = 71958517 is a prime.

It is not a weakly prime, because it can be changed into another prime (71958511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35979260 + 35979261.

It is an arithmetic number, because the mean of its divisors is an integer number (35979261).

Almost surely, 2^71958521 is an apocalyptic number.

It is an amenable number.

71958521 is a deficient number, since it is larger than the sum of its proper divisors (1).

71958521 is an equidigital number, since it uses as much as digits as its factorization.

71958521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25200, while the sum is 38.

The square root of 71958521 is about 8482.8368486020. The cubic root of 71958521 is about 415.9368605634.

The spelling of 71958521 in words is "seventy-one million, nine hundred fifty-eight thousand, five hundred twenty-one".