642307949 has 2 divisors, whose sum is σ = 642307950. Its totient is φ = 642307948.

The previous prime is 642307909. The next prime is 642307987. The reversal of 642307949 is 949703246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 384865924 + 257442025 = 19618^2 + 16045^2 .

It is a cyclic number.

It is not a de Polignac number, because 642307949 - 2¹² = 642303853 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642307909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321153974 + 321153975.

It is an arithmetic number, because the mean of its divisors is an integer number (321153975).

Almost surely, 2^642307949 is an apocalyptic number.

It is an amenable number.

642307949 is a deficient number, since it is larger than the sum of its proper divisors (1).

642307949 is an equidigital number, since it uses as much as digits as its factorization.

642307949 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 326592, while the sum is 44.

The square root of 642307949 is about 25343.7950788748. The cubic root of 642307949 is about 862.8085344121.

The spelling of 642307949 in words is "six hundred forty-two million, three hundred seven thousand, nine hundred forty-nine".