51669978 has 8 divisors (see below), whose sum is σ = 103339968. Its totient is φ = 17223324.

The previous prime is 51669977. The next prime is 51669991. The reversal of 51669978 is 87996615.

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

51669978 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 51669978.

It is not an unprimeable number, because it can be changed into a prime (51669971) 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, 4305826 + ... + 4305837.

It is an arithmetic number, because the mean of its divisors is an integer number (12917496).

Almost surely, 2^51669978 is an apocalyptic number.

51669978 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51669978 is a wasteful number, since it uses less digits than its factorization.

51669978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8611668.

The product of its digits is 816480, while the sum is 51.

The square root of 51669978 is about 7188.1832197016. The cubic root of 51669978 is about 372.4598169948.

The spelling of 51669978 in words is "fifty-one million, six hundred sixty-nine thousand, nine hundred seventy-eight".