642432423253 has 4 divisors (see below), whose sum is σ = 642434559660. Its totient is φ = 642430286848.

The previous prime is 642432423223. The next prime is 642432423271. The reversal of 642432423253 is 352324234246.

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 352102197924 + 290330225329 = 593382^2 + 538823^2 .

It is a cyclic number.

It is not a de Polignac number, because 642432423253 - 2¹³ = 642432415061 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 (642432423203) 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, 525100 + ... + 1249237.

It is an arithmetic number, because the mean of its divisors is an integer number (160608639915).

Almost surely, 2^642432423253 is an apocalyptic number.

It is an amenable number.

642432423253 is a deficient number, since it is larger than the sum of its proper divisors (2136407).

642432423253 is a wasteful number, since it uses less digits than its factorization.

642432423253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2136406.

The product of its digits is 829440, while the sum is 40.

Adding to 642432423253 its reverse (352324234246), we get a palindrome (994756657499).

The spelling of 642432423253 in words is "six hundred forty-two billion, four hundred thirty-two million, four hundred twenty-three thousand, two hundred fifty-three".