131221763 has 2 divisors, whose sum is σ = 131221764. Its totient is φ = 131221762.

The previous prime is 131221757. The next prime is 131221789. The reversal of 131221763 is 367122131.

It is an a-pointer prime, because the next prime (131221789) can be obtained adding 131221763 to its sum of digits (26).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 131221763 - 2⁸ = 131221507 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (131221063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65610881 + 65610882.

It is an arithmetic number, because the mean of its divisors is an integer number (65610882).

Almost surely, 2^131221763 is an apocalyptic number.

131221763 is a deficient number, since it is larger than the sum of its proper divisors (1).

131221763 is an equidigital number, since it uses as much as digits as its factorization.

131221763 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1512, while the sum is 26.

The square root of 131221763 is about 11455.2068073868. The cubic root of 131221763 is about 508.1617313695.

Adding to 131221763 its reverse (367122131), we get a palindrome (498343894).

The spelling of 131221763 in words is "one hundred thirty-one million, two hundred twenty-one thousand, seven hundred sixty-three".