51805494 has 80 divisors (see below), whose sum is σ = 132457248. Its totient is φ = 14992128.

The previous prime is 51805489. The next prime is 51805517. The reversal of 51805494 is 49450815.

51805494 is a `hidden beast` number, since 518 + 0 + 54 + 94 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 35079 + ... + 36525.

Almost surely, 2^51805494 is an apocalyptic number.

51805494 is a gapful number since it is divisible by the number (54) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 51805494, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66228624).

51805494 is an abundant number, since it is smaller than the sum of its proper divisors (80651754).

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

51805494 is a wasteful number, since it uses less digits than its factorization.

51805494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1491 (or 1482 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The square root of 51805494 is about 7197.6033511163. The cubic root of 51805494 is about 372.7851522865.

The spelling of 51805494 in words is "fifty-one million, eight hundred five thousand, four hundred ninety-four".