642403253 has 4 divisors (see below), whose sum is σ = 644244300. Its totient is φ = 640562208.

The previous prime is 642403247. The next prime is 642403291. The reversal of 642403253 is 352304246.

642403253 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 426959569 + 215443684 = 20663^2 + 14678^2 .

It is a cyclic number.

It is not a de Polignac number, because 642403253 - 2¹² = 642399157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642403453) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 920000 + ... + 920697.

It is an arithmetic number, because the mean of its divisors is an integer number (161061075).

Almost surely, 2^642403253 is an apocalyptic number.

It is an amenable number.

642403253 is a deficient number, since it is larger than the sum of its proper divisors (1841047).

642403253 is a wasteful number, since it uses less digits than its factorization.

642403253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1841046.

The product of its (nonzero) digits is 17280, while the sum is 29.

The square root of 642403253 is about 25345.6752326704. The cubic root of 642403253 is about 862.8512060714.

Adding to 642403253 its reverse (352304246), we get a palindrome (994707499).

The spelling of 642403253 in words is "six hundred forty-two million, four hundred three thousand, two hundred fifty-three".