642689500 has 48 divisors (see below), whose sum is σ = 1406190240. Its totient is φ = 256608000.

The previous prime is 642689479. The next prime is 642689521. The reversal of 642689500 is 5986246.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (642689479) and next prime (642689521).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 439771 + ... + 441229.

It is an arithmetic number, because the mean of its divisors is an integer number (29295630).

Almost surely, 2^642689500 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642689500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (703095120).

642689500 is an abundant number, since it is smaller than the sum of its proper divisors (763500740).

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

642689500 is a wasteful number, since it uses less digits than its factorization.

642689500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2359 (or 2347 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 40.

The square root of 642689500 is about 25351.3214645706. The cubic root of 642689500 is about 862.9793456743.

The spelling of 642689500 in words is "six hundred forty-two million, six hundred eighty-nine thousand, five hundred".