642817013 has 2 divisors, whose sum is σ = 642817014. Its totient is φ = 642817012.

The previous prime is 642817009. The next prime is 642817027. The reversal of 642817013 is 310718246.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 633126244 + 9690769 = 25162^2 + 3113^2 .

It is a cyclic number.

It is not a de Polignac number, because 642817013 - 2² = 642817009 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642817093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321408506 + 321408507.

It is an arithmetic number, because the mean of its divisors is an integer number (321408507).

Almost surely, 2^642817013 is an apocalyptic number.

It is an amenable number.

642817013 is a deficient number, since it is larger than the sum of its proper divisors (1).

642817013 is an equidigital number, since it uses as much as digits as its factorization.

642817013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 642817013 is about 25353.8362580498. The cubic root of 642817013 is about 863.0364151241.

The spelling of 642817013 in words is "six hundred forty-two million, eight hundred seventeen thousand, thirteen".