642786687246 has 64 divisors (see below), whose sum is σ = 1414931152896. Its totient is φ = 193052613600.

The previous prime is 642786687241. The next prime is 642786687271.

642786687246 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642786687241) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8267871 + ... + 8345253.

It is an arithmetic number, because the mean of its divisors is an integer number (22108299264).

Almost surely, 2^642786687246 is an apocalyptic number.

642786687246 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 642786687246, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (707465576448).

642786687246 is an abundant number, since it is smaller than the sum of its proper divisors (772144465650).

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

642786687246 is a wasteful number, since it uses less digits than its factorization.

642786687246 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78517.

The product of its digits is 260112384, while the sum is 66.

The spelling of 642786687246 in words is "six hundred forty-two billion, seven hundred eighty-six million, six hundred eighty-seven thousand, two hundred forty-six".