642197 has 2 divisors, whose sum is σ = 642198. Its totient is φ = 642196.

The previous prime is 642163. The next prime is 642199. The reversal of 642197 is 791246.

642197 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 398161 + 244036 = 631^2 + 494^2 .

It is a cyclic number.

It is not a de Polignac number, because 642197 - 2⁶ = 642133 is a prime.

It is a super-3 number, since 3×642197³ = 794558855033338119, which contains 333 as substring.

Together with 642199, it forms a pair of twin primes.

It is a Chen prime.

It is a nialpdrome in base 15.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 642197.

It is not a weakly prime, because it can be changed into another prime (642199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321098 + 321099.

It is an arithmetic number, because the mean of its divisors is an integer number (321099).

2⁶⁴²¹⁹⁷ is an apocalyptic number.

It is an amenable number.

642197 is a deficient number, since it is larger than the sum of its proper divisors (1).

642197 is an equidigital number, since it uses as much as digits as its factorization.

642197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3024, while the sum is 29.

The square root of 642197 is about 801.3719485982. The cubic root of 642197 is about 86.2758852502.

It can be divided in two parts, 64 and 2197, that multiplied together give a cube (140608 = 52³).

The spelling of 642197 in words is "six hundred forty-two thousand, one hundred ninety-seven".