197681842 has 4 divisors (see below), whose sum is σ = 296522766. Its totient is φ = 98840920.

The previous prime is 197681819. The next prime is 197681843. The reversal of 197681842 is 248186791.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 248186791 = 17 ⋅14599223.

It can be written as a sum of positive squares in only one way, i.e., 163353961 + 34327881 = 12781^2 + 5859^2 .

It is a super-2 number, since 2×197681842² = 78156221313025928, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 197681792 and 197681801.

It is not an unprimeable number, because it can be changed into a prime (197681843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49420459 + ... + 49420462.

Almost surely, 2^197681842 is an apocalyptic number.

197681842 is a deficient number, since it is larger than the sum of its proper divisors (98840924).

197681842 is an equidigital number, since it uses as much as digits as its factorization.

197681842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98840923.

The product of its digits is 193536, while the sum is 46.

The square root of 197681842 is about 14059.9374820801. The cubic root of 197681842 is about 582.5353163702.

The spelling of 197681842 in words is "one hundred ninety-seven million, six hundred eighty-one thousand, eight hundred forty-two".