194640981 has 8 divisors (see below), whose sum is σ = 265851264. Its totient is φ = 126595680.

The previous prime is 194640967. The next prime is 194641001. The reversal of 194640981 is 189046491.

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

It is not a de Polignac number, because 194640981 - 2¹⁰ = 194639957 is a prime.

It is a super-2 number, since 2×194640981² = 75770222969284722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (194640781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 791101 + ... + 791346.

It is an arithmetic number, because the mean of its divisors is an integer number (33231408).

Almost surely, 2^194640981 is an apocalyptic number.

It is an amenable number.

194640981 is a deficient number, since it is larger than the sum of its proper divisors (71210283).

194640981 is a wasteful number, since it uses less digits than its factorization.

194640981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1582491.

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 194640981 is about 13951.3791791349. The cubic root of 194640981 is about 579.5328987937.

The spelling of 194640981 in words is "one hundred ninety-four million, six hundred forty thousand, nine hundred eighty-one".