194991481 has 4 divisors (see below), whose sum is σ = 196068964. Its totient is φ = 193914000.

The previous prime is 194991469. The next prime is 194991487. The reversal of 194991481 is 184199491.

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 5103081 + 189888400 = 2259^2 + 13780^2 .

It is a cyclic number.

It is not a de Polignac number, because 194991481 - 2⁷ = 194991353 is a prime.

It is a super-2 number, since 2×194991481² = 76043355325146722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (194991487) 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, 538470 + ... + 538831.

It is an arithmetic number, because the mean of its divisors is an integer number (49017241).

Almost surely, 2^194991481 is an apocalyptic number.

It is an amenable number.

194991481 is a deficient number, since it is larger than the sum of its proper divisors (1077483).

194991481 is a wasteful number, since it uses less digits than its factorization.

194991481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1077482.

The product of its digits is 93312, while the sum is 46.

The square root of 194991481 is about 13963.9350113068. The cubic root of 194991481 is about 579.8805550703.

The spelling of 194991481 in words is "one hundred ninety-four million, nine hundred ninety-one thousand, four hundred eighty-one".