158042021 has 2 divisors, whose sum is σ = 158042022. Its totient is φ = 158042020.

The previous prime is 158041997. The next prime is 158042041. The reversal of 158042021 is 120240851.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 151019521 + 7022500 = 12289^2 + 2650^2 .

It is an emirp because it is prime and its reverse (120240851) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 158042021 - 2²² = 153847717 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (158042041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79021010 + 79021011.

It is an arithmetic number, because the mean of its divisors is an integer number (79021011).

Almost surely, 2^158042021 is an apocalyptic number.

It is an amenable number.

158042021 is a deficient number, since it is larger than the sum of its proper divisors (1).

158042021 is an equidigital number, since it uses as much as digits as its factorization.

158042021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 158042021 is about 12571.4764844866. The cubic root of 158042021 is about 540.6599396087.

Adding to 158042021 its reverse (120240851), we get a palindrome (278282872).

The spelling of 158042021 in words is "one hundred fifty-eight million, forty-two thousand, twenty-one".