518121407 has 4 divisors (see below), whose sum is σ = 521016120. Its totient is φ = 515226696.

The previous prime is 518121353. The next prime is 518121413. The reversal of 518121407 is 704121815.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 704121815 = 5 ⋅140824363.

It is a cyclic number.

It is not a de Polignac number, because 518121407 - 2⁶ = 518121343 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 518121407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (518121907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1447088 + ... + 1447445.

It is an arithmetic number, because the mean of its divisors is an integer number (130254030).

Almost surely, 2^518121407 is an apocalyptic number.

518121407 is a deficient number, since it is larger than the sum of its proper divisors (2894713).

518121407 is a wasteful number, since it uses less digits than its factorization.

518121407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2894712.

The product of its (nonzero) digits is 2240, while the sum is 29.

The square root of 518121407 is about 22762.2803558870. The cubic root of 518121407 is about 803.1756105055.

It can be divided in two parts, 518 and 121407, that multiplied together give a palindrome (62888826).

The spelling of 518121407 in words is "five hundred eighteen million, one hundred twenty-one thousand, four hundred seven".