158981905 has 4 divisors (see below), whose sum is σ = 190778292. Its totient is φ = 127185520.

The previous prime is 158981903. The next prime is 158981917. The reversal of 158981905 is 509189851.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 74028816 + 84953089 = 8604^2 + 9217^2 .

It is not a de Polignac number, because 158981905 - 2¹ = 158981903 is a prime.

It is a super-2 number, since 2×158981905² = 50550492234858050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (158981903) 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, 15898186 + ... + 15898195.

It is an arithmetic number, because the mean of its divisors is an integer number (47694573).

Almost surely, 2^158981905 is an apocalyptic number.

It is an amenable number.

158981905 is a deficient number, since it is larger than the sum of its proper divisors (31796387).

158981905 is an equidigital number, since it uses as much as digits as its factorization.

158981905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31796386.

The product of its (nonzero) digits is 129600, while the sum is 46.

The square root of 158981905 is about 12608.8026790810. The cubic root of 158981905 is about 541.7295994204.

The spelling of 158981905 in words is "one hundred fifty-eight million, nine hundred eighty-one thousand, nine hundred five".