1918798642 has 4 divisors (see below), whose sum is σ = 2878197966. Its totient is φ = 959399320.

The previous prime is 1918798631. The next prime is 1918798669. The reversal of 1918798642 is 2468978191.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2468978191 = 29 ⋅85137179.

It can be written as a sum of positive squares in only one way, i.e., 1736305561 + 182493081 = 41669^2 + 13509^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 479699659 + ... + 479699662.

Almost surely, 2^1918798642 is an apocalyptic number.

1918798642 is a deficient number, since it is larger than the sum of its proper divisors (959399324).

1918798642 is an equidigital number, since it uses as much as digits as its factorization.

1918798642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 959399323.

The product of its digits is 1741824, while the sum is 55.

The square root of 1918798642 is about 43804.0938954340. The cubic root of 1918798642 is about 1242.6337192241.

The spelling of 1918798642 in words is "one billion, nine hundred eighteen million, seven hundred ninety-eight thousand, six hundred forty-two".