971878261 has 2 divisors, whose sum is σ = 971878262. Its totient is φ = 971878260.

The previous prime is 971878249. The next prime is 971878283. The reversal of 971878261 is 162878179.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 606686161 + 365192100 = 24631^2 + 19110^2 .

It is a cyclic number.

It is not a de Polignac number, because 971878261 - 2¹⁵ = 971845493 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (971872261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 485939130 + 485939131.

It is an arithmetic number, because the mean of its divisors is an integer number (485939131).

Almost surely, 2^971878261 is an apocalyptic number.

It is an amenable number.

971878261 is a deficient number, since it is larger than the sum of its proper divisors (1).

971878261 is an equidigital number, since it uses as much as digits as its factorization.

971878261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 338688, while the sum is 49.

The square root of 971878261 is about 31174.9620849810. The cubic root of 971878261 is about 990.5368176618.

The spelling of 971878261 in words is "nine hundred seventy-one million, eight hundred seventy-eight thousand, two hundred sixty-one".