196742821 has 4 divisors (see below), whose sum is σ = 214628544. Its totient is φ = 178857100.

The previous prime is 196742803. The next prime is 196742881. The reversal of 196742821 is 128247691.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 196742821 - 2⁵ = 196742789 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (196742881) 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, 8942845 + ... + 8942866.

It is an arithmetic number, because the mean of its divisors is an integer number (53657136).

Almost surely, 2^196742821 is an apocalyptic number.

196742821 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

196742821 is a deficient number, since it is larger than the sum of its proper divisors (17885723).

196742821 is a wasteful number, since it uses less digits than its factorization.

196742821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17885722.

The product of its digits is 48384, while the sum is 40.

The square root of 196742821 is about 14026.5042330582. The cubic root of 196742821 is about 581.6114727566.

The spelling of 196742821 in words is "one hundred ninety-six million, seven hundred forty-two thousand, eight hundred twenty-one".