51378633 has 12 divisors (see below), whose sum is σ = 76773060. Its totient is φ = 33071136.

The previous prime is 51378623. The next prime is 51378659. The reversal of 51378633 is 33687315.

51378633 is a `hidden beast` number, since 5 + 13 + 7 + 8 + 633 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 30338064 + 21040569 = 5508^2 + 4587^2 .

It is not a de Polignac number, because 51378633 - 2⁵ = 51378601 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51378623) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 98166 + ... + 98687.

It is an arithmetic number, because the mean of its divisors is an integer number (6397755).

Almost surely, 2^51378633 is an apocalyptic number.

It is an amenable number.

51378633 is a deficient number, since it is larger than the sum of its proper divisors (25394427).

51378633 is a wasteful number, since it uses less digits than its factorization.

51378633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196888 (or 196885 counting only the distinct ones).

The product of its digits is 45360, while the sum is 36.

The square root of 51378633 is about 7167.8890197882. The cubic root of 51378633 is about 371.7584496747.

The spelling of 51378633 in words is "fifty-one million, three hundred seventy-eight thousand, six hundred thirty-three".