131878777 has 2 divisors, whose sum is σ = 131878778. Its totient is φ = 131878776.

The previous prime is 131878751. The next prime is 131878781. The reversal of 131878777 is 777878131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 69405561 + 62473216 = 8331^2 + 7904^2 .

It is a cyclic number.

It is not a de Polignac number, because 131878777 - 2¹⁵ = 131846009 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 131878777.

It is not a weakly prime, because it can be changed into another prime (131878717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65939388 + 65939389.

It is an arithmetic number, because the mean of its divisors is an integer number (65939389).

Almost surely, 2^131878777 is an apocalyptic number.

It is an amenable number.

131878777 is a deficient number, since it is larger than the sum of its proper divisors (1).

131878777 is an equidigital number, since it uses as much as digits as its factorization.

131878777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 460992, while the sum is 49.

The square root of 131878777 is about 11483.8485273884. The cubic root of 131878777 is about 509.0084245103.

The spelling of 131878777 in words is "one hundred thirty-one million, eight hundred seventy-eight thousand, seven hundred seventy-seven".