642645340 has 48 divisors (see below), whose sum is σ = 1362584160. Its totient is φ = 254592000.

The previous prime is 642645313. The next prime is 642645343. The reversal of 642645340 is 43546246.

It is a junction number, because it is equal to n+sod(n) for n = 642645296 and 642645305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642645343) 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, 1571056 + ... + 1571464.

It is an arithmetic number, because the mean of its divisors is an integer number (28387170).

Almost surely, 2^642645340 is an apocalyptic number.

It is an amenable number.

642645340 is an abundant number, since it is smaller than the sum of its proper divisors (719938820).

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

642645340 is a wasteful number, since it uses less digits than its factorization.

642645340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 982 (or 980 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 34.

The square root of 642645340 is about 25350.4504890939. The cubic root of 642645340 is about 862.9595797579.

The spelling of 642645340 in words is "six hundred forty-two million, six hundred forty-five thousand, three hundred forty".