642140540 has 24 divisors (see below), whose sum is σ = 1349335680. Its totient is φ = 256696128.

The previous prime is 642140531. The next prime is 642140561. The reversal of 642140540 is 45041246.

It is a super-2 number, since 2×642140540² = 824688946222983200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26054 + ... + 44306.

It is an arithmetic number, because the mean of its divisors is an integer number (56222320).

Almost surely, 2^642140540 is an apocalyptic number.

It is an amenable number.

642140540 is an abundant number, since it is smaller than the sum of its proper divisors (707195140).

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

642140540 is a wasteful number, since it uses less digits than its factorization.

642140540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20021 (or 20019 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 642140540 is about 25340.4921025619. The cubic root of 642140540 is about 862.7335680532.

Adding to 642140540 its reverse (45041246), we get a palindrome (687181786).

The spelling of 642140540 in words is "six hundred forty-two million, one hundred forty thousand, five hundred forty".