642795340 has 48 divisors (see below), whose sum is σ = 1481185440. Its totient is φ = 232378880.

The previous prime is 642795337. The next prime is 642795341. The reversal of 642795340 is 43597246.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 642795293 and 642795302.

It is not an unprimeable number, because it can be changed into a prime (642795341) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29616 + ... + 46504.

It is an arithmetic number, because the mean of its divisors is an integer number (30858030).

Almost surely, 2^642795340 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 642795340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (740592720).

642795340 is an abundant number, since it is smaller than the sum of its proper divisors (838390100).

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

642795340 is a wasteful number, since it uses less digits than its factorization.

642795340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17082 (or 17080 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 40.

The square root of 642795340 is about 25353.4088437827. The cubic root of 642795340 is about 863.0267157343.

The spelling of 642795340 in words is "six hundred forty-two million, seven hundred ninety-five thousand, three hundred forty".