51481216 has 16 divisors (see below), whose sum is σ = 102560490. Its totient is φ = 25740544.

The previous prime is 51481201. The next prime is 51481223. The reversal of 51481216 is 61218415.

It can be written as a sum of positive squares in only one way, i.e., 47886400 + 3594816 = 6920^2 + 1896^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200971 + ... + 201226.

Almost surely, 2^51481216 is an apocalyptic number.

It is an amenable number.

51481216 is a deficient number, since it is larger than the sum of its proper divisors (51079274).

51481216 is an equidigital number, since it uses as much as digits as its factorization.

51481216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402211 (or 402199 counting only the distinct ones).

The product of its digits is 1920, while the sum is 28.

The square root of 51481216 is about 7175.0411845508. The cubic root of 51481216 is about 372.0057038475.

The spelling of 51481216 in words is "fifty-one million, four hundred eighty-one thousand, two hundred sixteen".