642516444 has 36 divisors (see below), whose sum is σ = 1624967344. Its totient is φ = 214062912.

The previous prime is 642516439. The next prime is 642516451. The reversal of 642516444 is 444615246.

642516444 is a `hidden beast` number, since 6 + 4 + 2 + 5 + 1 + 644 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 642516399 and 642516408.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 99729 + ... + 105975.

Almost surely, 2^642516444 is an apocalyptic number.

It is an amenable number.

642516444 is an abundant number, since it is smaller than the sum of its proper divisors (982450900).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642516444 is a wasteful number, since it uses less digits than its factorization.

642516444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9114 (or 9109 counting only the distinct ones).

The product of its digits is 92160, while the sum is 36.

The square root of 642516444 is about 25347.9080793662. The cubic root of 642516444 is about 862.9018810198.

The spelling of 642516444 in words is "six hundred forty-two million, five hundred sixteen thousand, four hundred forty-four".