3956158421 has 2 divisors, whose sum is σ = 3956158422. Its totient is φ = 3956158420.

The previous prime is 3956158391. The next prime is 3956158441. The reversal of 3956158421 is 1248516593.

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., 3930036100 + 26122321 = 62690^2 + 5111^2 .

It is a cyclic number.

It is not a de Polignac number, because 3956158421 - 2¹⁴ = 3956142037 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3956158441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1978079210 + 1978079211.

It is an arithmetic number, because the mean of its divisors is an integer number (1978079211).

Almost surely, 2^3956158421 is an apocalyptic number.

It is an amenable number.

3956158421 is a deficient number, since it is larger than the sum of its proper divisors (1).

3956158421 is an equidigital number, since it uses as much as digits as its factorization.

3956158421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 259200, while the sum is 44.

The square root of 3956158421 is about 62898.0001351394. Note that the first 3 decimals coincide. The cubic root of 3956158421 is about 1581.5802196267.

The spelling of 3956158421 in words is "three billion, nine hundred fifty-six million, one hundred fifty-eight thousand, four hundred twenty-one".