642338825 has 12 divisors (see below), whose sum is σ = 831131328. Its totient is φ = 491528400.

The previous prime is 642338821. The next prime is 642338831. The reversal of 642338825 is 528833246.

It is not a de Polignac number, because 642338825 - 2² = 642338821 is a prime.

It is a super-2 number, since 2×642338825² = 825198332204761250, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642338821) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 557981 + ... + 559130.

It is an arithmetic number, because the mean of its divisors is an integer number (69260944).

Almost surely, 2^642338825 is an apocalyptic number.

It is an amenable number.

642338825 is a deficient number, since it is larger than the sum of its proper divisors (188792503).

642338825 is a wasteful number, since it uses less digits than its factorization.

642338825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1117144 (or 1117139 counting only the distinct ones).

The product of its digits is 276480, while the sum is 41.

The square root of 642338825 is about 25344.4042147374. The cubic root of 642338825 is about 862.8223593743.

The spelling of 642338825 in words is "six hundred forty-two million, three hundred thirty-eight thousand, eight hundred twenty-five".