518989642 has 4 divisors (see below), whose sum is σ = 778484466. Its totient is φ = 259494820.

The previous prime is 518989637. The next prime is 518989649. The reversal of 518989642 is 246989815.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 246989815 = 5 ⋅49397963.

It can be written as a sum of positive squares in only one way, i.e., 460145401 + 58844241 = 21451^2 + 7671^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 518989642.

It is not an unprimeable number, because it can be changed into a prime (518989649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 129747409 + ... + 129747412.

Almost surely, 2^518989642 is an apocalyptic number.

518989642 is a deficient number, since it is larger than the sum of its proper divisors (259494824).

518989642 is a wasteful number, since it uses less digits than its factorization.

518989642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259494823.

The product of its digits is 1244160, while the sum is 52.

The square root of 518989642 is about 22781.3441657862. The cubic root of 518989642 is about 803.6239970591.

The spelling of 518989642 in words is "five hundred eighteen million, nine hundred eighty-nine thousand, six hundred forty-two".