51491886 has 8 divisors (see below), whose sum is σ = 102983784. Its totient is φ = 17163960.

The previous prime is 51491857. The next prime is 51491933. The reversal of 51491886 is 68819415.

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

51491886 is an admirable number.

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, 4290985 + ... + 4290996.

It is an arithmetic number, because the mean of its divisors is an integer number (12872973).

Almost surely, 2^51491886 is an apocalyptic number.

51491886 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.

51491886 is a wasteful number, since it uses less digits than its factorization.

51491886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8581986.

The product of its digits is 69120, while the sum is 42.

The square root of 51491886 is about 7175.7846957667. The cubic root of 51491886 is about 372.0314027138.

The spelling of 51491886 in words is "fifty-one million, four hundred ninety-one thousand, eight hundred eighty-six".