197561851 has 2 divisors, whose sum is σ = 197561852. Its totient is φ = 197561850.

The previous prime is 197561843. The next prime is 197561887. The reversal of 197561851 is 158165791.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 197561851 - 2³ = 197561843 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 197561798 and 197561807.

It is not a weakly prime, because it can be changed into another prime (192561851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98780925 + 98780926.

It is an arithmetic number, because the mean of its divisors is an integer number (98780926).

Almost surely, 2^197561851 is an apocalyptic number.

197561851 is a deficient number, since it is larger than the sum of its proper divisors (1).

197561851 is an equidigital number, since it uses as much as digits as its factorization.

197561851 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75600, while the sum is 43.

The square root of 197561851 is about 14055.6697101205. The cubic root of 197561851 is about 582.4174280471.

The spelling of 197561851 in words is "one hundred ninety-seven million, five hundred sixty-one thousand, eight hundred fifty-one".