51208778 has 4 divisors (see below), whose sum is σ = 76813170. Its totient is φ = 25604388.

The previous prime is 51208763. The next prime is 51208783. The reversal of 51208778 is 87780215.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87780215 = 5 ⋅17556043.

It can be written as a sum of positive squares in only one way, i.e., 27071209 + 24137569 = 5203^2 + 4913^2 .

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 as a sum of consecutive naturals, namely, 12802193 + ... + 12802196.

Almost surely, 2^51208778 is an apocalyptic number.

51208778 is a deficient number, since it is larger than the sum of its proper divisors (25604392).

51208778 is a wasteful number, since it uses less digits than its factorization.

51208778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25604391.

The product of its (nonzero) digits is 31360, while the sum is 38.

The square root of 51208778 is about 7156.0308831083. The cubic root of 51208778 is about 371.3483262404.

The spelling of 51208778 in words is "fifty-one million, two hundred eight thousand, seven hundred seventy-eight".