642216040 has 32 divisors (see below), whose sum is σ = 1464787080. Its totient is φ = 253366272.

The previous prime is 642216011. The next prime is 642216041. The reversal of 642216040 is 40612246.

It can be written as a sum of positive squares in 4 ways, for example, as 560458276 + 81757764 = 23674^2 + 9042^2 .

It is a junction number, because it is equal to n+sod(n) for n = 642215996 and 642216014.

It is not an unprimeable number, because it can be changed into a prime (642216041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 107049 + ... + 112888.

Almost surely, 2^642216040 is an apocalyptic number.

It is an amenable number.

642216040 is an abundant number, since it is smaller than the sum of its proper divisors (822571040).

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

642216040 is a wasteful number, since it uses less digits than its factorization.

642216040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220021 (or 220017 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 642216040 is about 25341.9817693881. The cubic root of 642216040 is about 862.7673788405.

Adding to 642216040 its reverse (40612246), we get a palindrome (682828286).

The spelling of 642216040 in words is "six hundred forty-two million, two hundred sixteen thousand, forty".