97830781 has 2 divisors, whose sum is σ = 97830782. Its totient is φ = 97830780.

The previous prime is 97830749. The next prime is 97830793. The reversal of 97830781 is 18703879.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 94750756 + 3080025 = 9734^2 + 1755^2 .

It is a cyclic number.

It is not a de Polignac number, because 97830781 - 2⁵ = 97830749 is a prime.

It is a super-2 number, since 2×97830781² = 19141723422139922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (97830181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 48915390 + 48915391.

It is an arithmetic number, because the mean of its divisors is an integer number (48915391).

Almost surely, 2^97830781 is an apocalyptic number.

It is an amenable number.

97830781 is a deficient number, since it is larger than the sum of its proper divisors (1).

97830781 is an equidigital number, since it uses as much as digits as its factorization.

97830781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84672, while the sum is 43.

The square root of 97830781 is about 9890.9443937371. The cubic root of 97830781 is about 460.7781112132.

The spelling of 97830781 in words is "ninety-seven million, eight hundred thirty thousand, seven hundred eighty-one".