642686352 has 120 divisors (see below), whose sum is σ = 2106999072. Its totient is φ = 166924800.

The previous prime is 642686339. The next prime is 642686353. The reversal of 642686352 is 253686246.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (642686353) 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, 13452 + ... + 38292.

Almost surely, 2^642686352 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 642686352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1053499536).

642686352 is an abundant number, since it is smaller than the sum of its proper divisors (1464312720).

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

642686352 is a wasteful number, since it uses less digits than its factorization.

642686352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24877 (or 24864 counting only the distinct ones).

The product of its digits is 414720, while the sum is 42.

The square root of 642686352 is about 25351.2593770014. The cubic root of 642686352 is about 862.9779366666.

The spelling of 642686352 in words is "six hundred forty-two million, six hundred eighty-six thousand, three hundred fifty-two".