51978518 has 8 divisors (see below), whose sum is σ = 78193512. Its totient is φ = 25914016.

The previous prime is 51978499. The next prime is 51978523. The reversal of 51978518 is 81587915.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36755 + ... + 38142.

It is an arithmetic number, because the mean of its divisors is an integer number (9774189).

Almost surely, 2^51978518 is an apocalyptic number.

51978518 is a deficient number, since it is larger than the sum of its proper divisors (26214994).

51978518 is a wasteful number, since it uses less digits than its factorization.

51978518 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75246.

The product of its digits is 100800, while the sum is 44.

The square root of 51978518 is about 7209.6128883595. The cubic root of 51978518 is about 373.1997100095.

The spelling of 51978518 in words is "fifty-one million, nine hundred seventy-eight thousand, five hundred eighteen".