642041663 has 2 divisors, whose sum is σ = 642041664. Its totient is φ = 642041662.

The previous prime is 642041657. The next prime is 642041677. The reversal of 642041663 is 366140246.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 642041663 - 2¹⁰ = 642040639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642041633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321020831 + 321020832.

It is an arithmetic number, because the mean of its divisors is an integer number (321020832).

Almost surely, 2^642041663 is an apocalyptic number.

642041663 is a deficient number, since it is larger than the sum of its proper divisors (1).

642041663 is an equidigital number, since it uses as much as digits as its factorization.

642041663 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 32.

The square root of 642041663 is about 25338.5410590271. The cubic root of 642041663 is about 862.6892844525.

The spelling of 642041663 in words is "six hundred forty-two million, forty-one thousand, six hundred sixty-three".