194295721 has 9 divisors (see below), whose sum is σ = 198786679. Its totient is φ = 189904936.

The previous prime is 194295713. The next prime is 194295727. The reversal of 194295721 is 127592491.

It is a happy number.

The square root of 194295721 is 13939.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 140067225 + 54228496 = 11835^2 + 7364^2 .

It is not a de Polignac number, because 194295721 - 2³ = 194295713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (194295727) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 738636 + ... + 738898.

Almost surely, 2^194295721 is an apocalyptic number.

194295721 is the 13939-th square number.

194295721 is the 6970-th centered octagonal number.

It is an amenable number.

194295721 is a deficient number, since it is larger than the sum of its proper divisors (4490958).

194295721 is an frugal number, since it uses more digits than its factorization.

194295721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 632 (or 316 counting only the distinct ones).

The product of its digits is 45360, while the sum is 40.

The cubic root of 194295721 is about 579.1900317150.

The spelling of 194295721 in words is "one hundred ninety-four million, two hundred ninety-five thousand, seven hundred twenty-one".