97501561 has 2 divisors, whose sum is σ = 97501562. Its totient is φ = 97501560.

The previous prime is 97501543. The next prime is 97501601. The reversal of 97501561 is 16510579.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 97219600 + 281961 = 9860^2 + 531^2 .

It is an emirp because it is prime and its reverse (16510579) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 97501561 - 2⁹ = 97501049 is a prime.

It is not a weakly prime, because it can be changed into another prime (97501361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 48750780 + 48750781.

It is an arithmetic number, because the mean of its divisors is an integer number (48750781).

Almost surely, 2^97501561 is an apocalyptic number.

It is an amenable number.

97501561 is a deficient number, since it is larger than the sum of its proper divisors (1).

97501561 is an equidigital number, since it uses as much as digits as its factorization.

97501561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9450, while the sum is 34.

The square root of 97501561 is about 9874.2878730570. The cubic root of 97501561 is about 460.2606603966.

It can be divided in two parts, 9750 and 1561, that added together give a palindrome (11311).

The spelling of 97501561 in words is "ninety-seven million, five hundred one thousand, five hundred sixty-one".