158251421 has 2 divisors, whose sum is σ = 158251422. Its totient is φ = 158251420.

The previous prime is 158251411. The next prime is 158251441. The reversal of 158251421 is 124152851.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 156600196 + 1651225 = 12514^2 + 1285^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-158251421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (158251411) 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, 79125710 + 79125711.

It is an arithmetic number, because the mean of its divisors is an integer number (79125711).

Almost surely, 2^158251421 is an apocalyptic number.

It is an amenable number.

158251421 is a deficient number, since it is larger than the sum of its proper divisors (1).

158251421 is an equidigital number, since it uses as much as digits as its factorization.

158251421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3200, while the sum is 29.

The square root of 158251421 is about 12579.8021049617. The cubic root of 158251421 is about 540.8986192245.

The spelling of 158251421 in words is "one hundred fifty-eight million, two hundred fifty-one thousand, four hundred twenty-one".