51118618 has 4 divisors (see below), whose sum is σ = 76677930. Its totient is φ = 25559308.

The previous prime is 51118589. The next prime is 51118631. The reversal of 51118618 is 81681115.

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: 81681115 = 5 ⋅16336223.

It can be written as a sum of positive squares in only one way, i.e., 45657049 + 5461569 = 6757^2 + 2337^2 .

It is a super-2 number, since 2×51118618² = 5226226212459848, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51118618.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12779653 + ... + 12779656.

Almost surely, 2^51118618 is an apocalyptic number.

51118618 is a deficient number, since it is larger than the sum of its proper divisors (25559312).

51118618 is a wasteful number, since it uses less digits than its factorization.

51118618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25559311.

The product of its digits is 1920, while the sum is 31.

The square root of 51118618 is about 7149.7285263148. The cubic root of 51118618 is about 371.1302618460.

The spelling of 51118618 in words is "fifty-one million, one hundred eighteen thousand, six hundred eighteen".