4156042421 has 2 divisors, whose sum is σ = 4156042422. Its totient is φ = 4156042420.

The previous prime is 4156042409. The next prime is 4156042447. The reversal of 4156042421 is 1242406514.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2592235396 + 1563807025 = 50914^2 + 39545^2 .

It is a cyclic number.

It is not a de Polignac number, because 4156042421 - 2⁶ = 4156042357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4156042021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2078021210 + 2078021211.

It is an arithmetic number, because the mean of its divisors is an integer number (2078021211).

Almost surely, 2^4156042421 is an apocalyptic number.

It is an amenable number.

4156042421 is a deficient number, since it is larger than the sum of its proper divisors (1).

4156042421 is an equidigital number, since it uses as much as digits as its factorization.

4156042421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7680, while the sum is 29.

The square root of 4156042421 is about 64467.3748573649. The cubic root of 4156042421 is about 1607.7801307268.

Adding to 4156042421 its reverse (1242406514), we get a palindrome (5398448935).

The spelling of 4156042421 in words is "four billion, one hundred fifty-six million, forty-two thousand, four hundred twenty-one".