158165603 has 4 divisors (see below), whose sum is σ = 167469480. Its totient is φ = 148861728.

The previous prime is 158165593. The next prime is 158165611. The reversal of 158165603 is 306561851.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 306561851 = 3373 ⋅90887.

It is a cyclic number.

It is not a de Polignac number, because 158165603 - 2¹⁶ = 158100067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (158165803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4651913 + ... + 4651946.

It is an arithmetic number, because the mean of its divisors is an integer number (41867370).

Almost surely, 2^158165603 is an apocalyptic number.

158165603 is a deficient number, since it is larger than the sum of its proper divisors (9303877).

158165603 is an equidigital number, since it uses as much as digits as its factorization.

158165603 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9303876.

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 158165603 is about 12576.3906984476. The cubic root of 158165603 is about 540.8008270936.

It can be divided in two parts, 15 and 8165603, that added together give a palindrome (8165618).

The spelling of 158165603 in words is "one hundred fifty-eight million, one hundred sixty-five thousand, six hundred three".