193000021 has 4 divisors (see below), whose sum is σ = 193276044. Its totient is φ = 192724000.

The previous prime is 193000019. The next prime is 193000121. The reversal of 193000021 is 120000391.

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 117483921 + 75516100 = 10839^2 + 8690^2 .

It is a cyclic number.

It is not a de Polignac number, because 193000021 - 2¹ = 193000019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 192999959 and 193000004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (193000121) 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 3 ways as a sum of consecutive naturals, for example, 136960 + ... + 138361.

It is an arithmetic number, because the mean of its divisors is an integer number (48319011).

Almost surely, 2^193000021 is an apocalyptic number.

It is an amenable number.

193000021 is a deficient number, since it is larger than the sum of its proper divisors (276023).

193000021 is an equidigital number, since it uses as much as digits as its factorization.

193000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276022.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 193000021 is about 13892.4447452563. Note that the first 3 decimals coincide. The cubic root of 193000021 is about 577.8996774753.

The spelling of 193000021 in words is "one hundred ninety-three million, twenty-one", and thus it is an aban number.