197978101 has 4 divisors (see below), whose sum is σ = 198038304. Its totient is φ = 197917900.

The previous prime is 197978087. The next prime is 197978113. The reversal of 197978101 is 101879791.

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 197978101 - 2⁵ = 197978069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (197978191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24865 + ... + 31846.

It is an arithmetic number, because the mean of its divisors is an integer number (49509576).

Almost surely, 2^197978101 is an apocalyptic number.

It is an amenable number.

197978101 is a deficient number, since it is larger than the sum of its proper divisors (60203).

197978101 is an equidigital number, since it uses as much as digits as its factorization.

197978101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60202.

The product of its (nonzero) digits is 31752, while the sum is 43.

The square root of 197978101 is about 14070.4691108719. The cubic root of 197978101 is about 582.8261796860.

The spelling of 197978101 in words is "one hundred ninety-seven million, nine hundred seventy-eight thousand, one hundred one".