642542500 has 30 divisors (see below), whose sum is σ = 1405117406. Its totient is φ = 257016000.

The previous prime is 642542497. The next prime is 642542503. The reversal of 642542500 is 5245246.

It is an interprime number because it is at equal distance from previous prime (642542497) and next prime (642542503).

It can be written as a sum of positive squares in 5 ways, for example, as 452157696 + 190384804 = 21264^2 + 13798^2 .

It is not an unprimeable number, because it can be changed into a prime (642542503) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 126009 + ... + 131008.

Almost surely, 2^642542500 is an apocalyptic number.

It is an amenable number.

642542500 is an abundant number, since it is smaller than the sum of its proper divisors (762574906).

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

642542500 is a wasteful number, since it uses less digits than its factorization.

642542500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257041 (or 257024 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 28.

The square root of 642542500 is about 25348.4220416183. The cubic root of 642542500 is about 862.9135452959.

Adding to 642542500 its reverse (5245246), we get a palindrome (647787746).

The spelling of 642542500 in words is "six hundred forty-two million, five hundred forty-two thousand, five hundred".