642867652 has 36 divisors (see below), whose sum is σ = 1317537900. Its totient is φ = 273653184.

The previous prime is 642867647. The next prime is 642867671. The reversal of 642867652 is 256768246.

It can be written as a sum of positive squares in 2 ways, for example, as 245423556 + 397444096 = 15666^2 + 19936^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18198 + ... + 40210.

It is an arithmetic number, because the mean of its divisors is an integer number (36598275).

Almost surely, 2^642867652 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 642867652, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (658768950).

642867652 is an abundant number, since it is smaller than the sum of its proper divisors (674670248).

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

642867652 is a wasteful number, since it uses less digits than its factorization.

642867652 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22180 (or 22171 counting only the distinct ones).

The product of its digits is 967680, while the sum is 46.

The square root of 642867652 is about 25354.8348841005. The cubic root of 642867652 is about 863.0590769147.

The spelling of 642867652 in words is "six hundred forty-two million, eight hundred sixty-seven thousand, six hundred fifty-two".