642053641 has 2 divisors, whose sum is σ = 642053642. Its totient is φ = 642053640.

The previous prime is 642053627. The next prime is 642053647. The reversal of 642053641 is 146350246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 467813641 + 174240000 = 21629^2 + 13200^2 .

It is a cyclic number.

It is not a de Polignac number, because 642053641 - 2⁷ = 642053513 is a prime.

It is not a weakly prime, because it can be changed into another prime (642053647) 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, 321026820 + 321026821.

It is an arithmetic number, because the mean of its divisors is an integer number (321026821).

Almost surely, 2^642053641 is an apocalyptic number.

It is an amenable number.

642053641 is a deficient number, since it is larger than the sum of its proper divisors (1).

642053641 is an equidigital number, since it uses as much as digits as its factorization.

642053641 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 642053641 is about 25338.7774172315. Note that the first 3 decimals coincide. The cubic root of 642053641 is about 862.6946492279.

The spelling of 642053641 in words is "six hundred forty-two million, fifty-three thousand, six hundred forty-one".