51994647 has 6 divisors (see below), whose sum is σ = 75103392. Its totient is φ = 34663092.

The previous prime is 51994639. The next prime is 51994661. The reversal of 51994647 is 74649915.

51994647 is a `hidden beast` number, since 519 + 94 + 6 + 47 = 666.

It is not a de Polignac number, because 51994647 - 2³ = 51994639 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51994637) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 2888583 + ... + 2888600.

It is an arithmetic number, because the mean of its divisors is an integer number (12517232).

Almost surely, 2^51994647 is an apocalyptic number.

51994647 is a deficient number, since it is larger than the sum of its proper divisors (23108745).

51994647 is a wasteful number, since it uses less digits than its factorization.

51994647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5777189 (or 5777186 counting only the distinct ones).

The product of its digits is 272160, while the sum is 45.

The square root of 51994647 is about 7210.7313776066. The cubic root of 51994647 is about 373.2383074651.

The spelling of 51994647 in words is "fifty-one million, nine hundred ninety-four thousand, six hundred forty-seven".