642803868 has 72 divisors (see below), whose sum is σ = 1876204512. Its totient is φ = 181757952.

The previous prime is 642803867. The next prime is 642803869. The reversal of 642803868 is 868308246.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (642803867) and next prime (642803869).

It is a super-2 number, since 2×642803868² = 826393625431522848, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642803867) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11296 + ... + 37592.

It is an arithmetic number, because the mean of its divisors is an integer number (26058396).

Almost surely, 2^642803868 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 642803868, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (938102256).

642803868 is an abundant number, since it is smaller than the sum of its proper divisors (1233400644).

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

642803868 is a wasteful number, since it uses less digits than its factorization.

642803868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26411 (or 26406 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 45.

The square root of 642803868 is about 25353.5770257374. The cubic root of 642803868 is about 863.0305323245.

The spelling of 642803868 in words is "six hundred forty-two million, eight hundred three thousand, eight hundred sixty-eight".