158542721 has 8 divisors (see below), whose sum is σ = 161448000. Its totient is φ = 155647440.

The previous prime is 158542687. The next prime is 158542723. The reversal of 158542721 is 127245851.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 158542721 - 2²⁶ = 91433857 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (158542723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34370 + ... + 38708.

It is an arithmetic number, because the mean of its divisors is an integer number (20181000).

Almost surely, 2^158542721 is an apocalyptic number.

It is an amenable number.

158542721 is a deficient number, since it is larger than the sum of its proper divisors (2905279).

158542721 is an equidigital number, since it uses as much as digits as its factorization.

158542721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4999.

The product of its digits is 22400, while the sum is 35.

The square root of 158542721 is about 12591.3748653592. The cubic root of 158542721 is about 541.2303006874.

The spelling of 158542721 in words is "one hundred fifty-eight million, five hundred forty-two thousand, seven hundred twenty-one".