642420232 has 8 divisors (see below), whose sum is σ = 1204537950. Its totient is φ = 321210112.

The previous prime is 642420217. The next prime is 642420241. The reversal of 642420232 is 232024246.

It can be written as a sum of positive squares in only one way, i.e., 590781636 + 51638596 = 24306^2 + 7186^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 642420197 and 642420206.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40151257 + ... + 40151272.

Almost surely, 2^642420232 is an apocalyptic number.

It is an amenable number.

642420232 is a deficient number, since it is larger than the sum of its proper divisors (562117718).

642420232 is a wasteful number, since it uses less digits than its factorization.

642420232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80302535 (or 80302531 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 25.

The square root of 642420232 is about 25346.0101791189. The cubic root of 642420232 is about 862.8588078498.

Adding to 642420232 its reverse (232024246), we get a palindrome (874444478).

The spelling of 642420232 in words is "six hundred forty-two million, four hundred twenty thousand, two hundred thirty-two".