131228281 has 2 divisors, whose sum is σ = 131228282. Its totient is φ = 131228280.

The previous prime is 131228197. The next prime is 131228291. The reversal of 131228281 is 182822131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74978281 + 56250000 = 8659^2 + 7500^2 .

It is a cyclic number.

It is not a de Polignac number, because 131228281 - 2¹¹ = 131226233 is a prime.

It is a super-2 number, since 2×131228281² = 34441723468429922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (131228291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65614140 + 65614141.

It is an arithmetic number, because the mean of its divisors is an integer number (65614141).

Almost surely, 2^131228281 is an apocalyptic number.

It is an amenable number.

131228281 is a deficient number, since it is larger than the sum of its proper divisors (1).

131228281 is an equidigital number, since it uses as much as digits as its factorization.

131228281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1536, while the sum is 28.

The square root of 131228281 is about 11455.4913033008. The cubic root of 131228281 is about 508.1701449722.

The spelling of 131228281 in words is "one hundred thirty-one million, two hundred twenty-eight thousand, two hundred eighty-one".