51111439 has 4 divisors (see below), whose sum is σ = 51589224. Its totient is φ = 50633656.

The previous prime is 51111397. The next prime is 51111443. The reversal of 51111439 is 93411115.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51111439 - 2¹¹ = 51109391 is a prime.

It is a super-2 number, since 2×51111439² = 5224758393301442, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51111479) 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, 238732 + ... + 238945.

It is an arithmetic number, because the mean of its divisors is an integer number (12897306).

Almost surely, 2^51111439 is an apocalyptic number.

51111439 is a deficient number, since it is larger than the sum of its proper divisors (477785).

51111439 is a wasteful number, since it uses less digits than its factorization.

51111439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 477784.

The product of its digits is 540, while the sum is 25.

The square root of 51111439 is about 7149.2264616530. The cubic root of 51111439 is about 371.1128874269.

The spelling of 51111439 in words is "fifty-one million, one hundred eleven thousand, four hundred thirty-nine".