642501340 has 96 divisors (see below), whose sum is σ = 1548933120. Its totient is φ = 221895936.

The previous prime is 642501329. The next prime is 642501341. The reversal of 642501340 is 43105246.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642501341) 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, 409237 + ... + 410803.

It is an arithmetic number, because the mean of its divisors is an integer number (16134720).

Almost surely, 2^642501340 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 642501340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (774466560).

642501340 is an abundant number, since it is smaller than the sum of its proper divisors (906431780).

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

642501340 is a wasteful number, since it uses less digits than its factorization.

642501340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1691 (or 1689 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 642501340 is about 25347.6101437591. The cubic root of 642501340 is about 862.8951193915.

Adding to 642501340 its reverse (43105246), we get a palindrome (685606586).

The spelling of 642501340 in words is "six hundred forty-two million, five hundred one thousand, three hundred forty".