190978281 has 36 divisors (see below), whose sum is σ = 300524796. Its totient is φ = 116812800.

The previous prime is 190978243. The next prime is 190978297. The reversal of 190978281 is 182879091.

It can be written as a sum of positive squares in 6 ways, for example, as 24800400 + 166177881 = 4980^2 + 12891^2 .

It is not a de Polignac number, because 190978281 - 2¹³ = 190970089 is a prime.

It is a super-2 number, since 2×190978281² = 72945407627429922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (190978241) 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 35 ways as a sum of consecutive naturals, for example, 366301 + ... + 366821.

It is an arithmetic number, because the mean of its divisors is an integer number (8347911).

Almost surely, 2^190978281 is an apocalyptic number.

It is an amenable number.

190978281 is a deficient number, since it is larger than the sum of its proper divisors (109546515).

190978281 is a wasteful number, since it uses less digits than its factorization.

190978281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 794 (or 778 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 45.

The square root of 190978281 is about 13819.4891729036. The cubic root of 190978281 is about 575.8746924320.

The spelling of 190978281 in words is "one hundred ninety million, nine hundred seventy-eight thousand, two hundred eighty-one".