197661801 has 4 divisors (see below), whose sum is σ = 263549072. Its totient is φ = 131774532.

The previous prime is 197661749. The next prime is 197661803. The reversal of 197661801 is 108166791.

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 de Polignac number, because none of the positive numbers 2^k-197661801 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 197661801.

It is not an unprimeable number, because it can be changed into a prime (197661803) 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, 32943631 + ... + 32943636.

It is an arithmetic number, because the mean of its divisors is an integer number (65887268).

Almost surely, 2^197661801 is an apocalyptic number.

It is an amenable number.

197661801 is a deficient number, since it is larger than the sum of its proper divisors (65887271).

197661801 is an equidigital number, since it uses as much as digits as its factorization.

197661801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65887270.

The product of its (nonzero) digits is 18144, while the sum is 39.

The square root of 197661801 is about 14059.2247652564. The cubic root of 197661801 is about 582.5156298802.

The spelling of 197661801 in words is "one hundred ninety-seven million, six hundred sixty-one thousand, eight hundred one".