7961521 has 2 divisors, whose sum is σ = 7961522. Its totient is φ = 7961520.

The previous prime is 7961509. The next prime is 7961533. The reversal of 7961521 is 1251697.

It is a balanced prime because it is at equal distance from previous prime (7961509) and next prime (7961533).

It can be written as a sum of positive squares in only one way, i.e., 4579600 + 3381921 = 2140^2 + 1839^2 .

It is an emirp because it is prime and its reverse (1251697) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7961521 - 2⁵ = 7961489 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (7961561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3980760 + 3980761.

It is an arithmetic number, because the mean of its divisors is an integer number (3980761).

Almost surely, 2^7961521 is an apocalyptic number.

It is an amenable number.

7961521 is a deficient number, since it is larger than the sum of its proper divisors (1).

7961521 is an equidigital number, since it uses as much as digits as its factorization.

7961521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3780, while the sum is 31.

The square root of 7961521 is about 2821.6167351361. The cubic root of 7961521 is about 199.6788261796.

The spelling of 7961521 in words is "seven million, nine hundred sixty-one thousand, five hundred twenty-one".