51015808 has 32 divisors (see below), whose sum is σ = 104122620. Its totient is φ = 24883200.

The previous prime is 51015787. The next prime is 51015823. The reversal of 51015808 is 80851015.

It can be written as a sum of positive squares in 2 ways, for example, as 34951744 + 16064064 = 5912^2 + 4008^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a super-2 number, since 2×51015808² = 5205225331785728, which contains 22 as substring.

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, 388 + ... + 10108.

Almost surely, 2^51015808 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 51015808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52061310).

51015808 is an abundant number, since it is smaller than the sum of its proper divisors (53106812).

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

51015808 is an equidigital number, since it uses as much as digits as its factorization.

51015808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9776 (or 9764 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 28.

The square root of 51015808 is about 7142.5351241698. The cubic root of 51015808 is about 370.8812885619.

The spelling of 51015808 in words is "fifty-one million, fifteen thousand, eight hundred eight".