51978519 has 12 divisors (see below), whose sum is σ = 75255336. Its totient is φ = 34571472.

The previous prime is 51978499. The next prime is 51978523. The reversal of 51978519 is 91587915.

It is not a de Polignac number, because 51978519 - 2¹¹ = 51976471 is a prime.

It is a super-2 number, since 2×51978519² = 5403532874866722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51978559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2532 + ... + 10505.

It is an arithmetic number, because the mean of its divisors is an integer number (6271278).

Almost surely, 2^51978519 is an apocalyptic number.

51978519 is a deficient number, since it is larger than the sum of its proper divisors (23276817).

51978519 is a wasteful number, since it uses less digits than its factorization.

51978519 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13486 (or 13483 counting only the distinct ones).

The product of its digits is 113400, while the sum is 45.

The square root of 51978519 is about 7209.6129577114. The cubic root of 51978519 is about 373.1997124028.

The spelling of 51978519 in words is "fifty-one million, nine hundred seventy-eight thousand, five hundred nineteen".