51261808 has 40 divisors (see below), whose sum is σ = 109586736. Its totient is φ = 23078400.

The previous prime is 51261797. The next prime is 51261823. The reversal of 51261808 is 80816215.

It is a self number, because there is not a number n which added to its sum of digits gives 51261808.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 5523 + ... + 11533.

It is a vampire number, since it can be written as 6011 ⋅ 8528 (with its own digits).

Almost surely, 2^51261808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51261808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54793368).

51261808 is an abundant number, since it is smaller than the sum of its proper divisors (58324928).

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

51261808 is a wasteful number, since it uses less digits than its factorization.

51261808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6073 (or 6067 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 31.

The square root of 51261808 is about 7159.7351906338. The cubic root of 51261808 is about 371.4764670837.

The spelling of 51261808 in words is "fifty-one million, two hundred sixty-one thousand, eight hundred eight".