197920906 has 4 divisors (see below), whose sum is σ = 296881362. Its totient is φ = 98960452.

The previous prime is 197920897. The next prime is 197920909. The reversal of 197920906 is 609029791.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 181037025 + 16883881 = 13455^2 + 4109^2 .

It is not an unprimeable number, because it can be changed into a prime (197920909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49480225 + ... + 49480228.

Almost surely, 2^197920906 is an apocalyptic number.

197920906 is a deficient number, since it is larger than the sum of its proper divisors (98960456).

197920906 is an equidigital number, since it uses as much as digits as its factorization.

197920906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98960455.

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 197920906 is about 14068.4365158322. The cubic root of 197920906 is about 582.7700489762.

The spelling of 197920906 in words is "one hundred ninety-seven million, nine hundred twenty thousand, nine hundred six".