4131981961 has 2 divisors, whose sum is σ = 4131981962. Its totient is φ = 4131981960.

The previous prime is 4131981859. The next prime is 4131981967. The reversal of 4131981961 is 1691891314.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3085135936 + 1046846025 = 55544^2 + 32355^2 .

It is a cyclic number.

It is not a de Polignac number, because 4131981961 - 2¹⁵ = 4131949193 is a prime.

It is not a weakly prime, because it can be changed into another prime (4131981967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2065990980 + 2065990981.

It is an arithmetic number, because the mean of its divisors is an integer number (2065990981).

Almost surely, 2^4131981961 is an apocalyptic number.

It is an amenable number.

4131981961 is a deficient number, since it is larger than the sum of its proper divisors (1).

4131981961 is an equidigital number, since it uses as much as digits as its factorization.

4131981961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46656, while the sum is 43.

The square root of 4131981961 is about 64280.4944053793. The cubic root of 4131981961 is about 1604.6714985858.

The spelling of 4131981961 in words is "four billion, one hundred thirty-one million, nine hundred eighty-one thousand, nine hundred sixty-one".