3995251261 has 2 divisors, whose sum is σ = 3995251262. Its totient is φ = 3995251260.

The previous prime is 3995251259. The next prime is 3995251291. The reversal of 3995251261 is 1621525993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3309125625 + 686125636 = 57525^2 + 26194^2 .

It is an emirp because it is prime and its reverse (1621525993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3995251261 - 2¹ = 3995251259 is a prime.

Together with 3995251259, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3995251291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1997625630 + 1997625631.

It is an arithmetic number, because the mean of its divisors is an integer number (1997625631).

Almost surely, 2^3995251261 is an apocalyptic number.

It is an amenable number.

3995251261 is a deficient number, since it is larger than the sum of its proper divisors (1).

3995251261 is an equidigital number, since it uses as much as digits as its factorization.

3995251261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145800, while the sum is 43.

The square root of 3995251261 is about 63207.9999762688. Note that the first 4 decimals coincide. The cubic root of 3995251261 is about 1586.7726237754.

The spelling of 3995251261 in words is "three billion, nine hundred ninety-five million, two hundred fifty-one thousand, two hundred sixty-one".