971521 has 2 divisors, whose sum is σ = 971522. Its totient is φ = 971520.

The previous prime is 971513. The next prime is 971549. The reversal of 971521 is 125179.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 970225 + 1296 = 985^2 + 36^2 .

It is a cyclic number.

It is not a de Polignac number, because 971521 - 2³ = 971513 is a prime.

It is equal to p₇₆₄₇₁ and since 971521 and 76471 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (971501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 485760 + 485761.

It is an arithmetic number, because the mean of its divisors is an integer number (485761).

2⁹⁷¹⁵²¹ is an apocalyptic number.

It is an amenable number.

971521 is a deficient number, since it is larger than the sum of its proper divisors (1).

971521 is an equidigital number, since it uses as much as digits as its factorization.

971521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 630, while the sum is 25.

The square root of 971521 is about 985.6576484764. The cubic root of 971521 is about 99.0415429501.

The spelling of 971521 in words is "nine hundred seventy-one thousand, five hundred twenty-one".