642217627477 has 2 divisors, whose sum is σ = 642217627478. Its totient is φ = 642217627476.

The previous prime is 642217627453. The next prime is 642217627559. The reversal of 642217627477 is 774726712246.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 642035215441 + 182412036 = 801271^2 + 13506^2 .

It is a cyclic number.

It is not a de Polignac number, because 642217627477 - 2¹¹ = 642217625429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642217627417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321108813738 + 321108813739.

It is an arithmetic number, because the mean of its divisors is an integer number (321108813739).

Almost surely, 2^642217627477 is an apocalyptic number.

It is an amenable number.

642217627477 is a deficient number, since it is larger than the sum of its proper divisors (1).

642217627477 is an equidigital number, since it uses as much as digits as its factorization.

642217627477 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11063808, while the sum is 55.

The spelling of 642217627477 in words is "six hundred forty-two billion, two hundred seventeen million, six hundred twenty-seven thousand, four hundred seventy-seven".