51689649 has 8 divisors (see below), whose sum is σ = 75184992. Its totient is φ = 31327040.

The previous prime is 51689647. The next prime is 51689657. The reversal of 51689649 is 94698615.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 51689649 - 2¹ = 51689647 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 51689598 and 51689607.

It is not an unprimeable number, because it can be changed into a prime (51689647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 783144 + ... + 783209.

It is an arithmetic number, because the mean of its divisors is an integer number (9398124).

Almost surely, 2^51689649 is an apocalyptic number.

It is an amenable number.

51689649 is a deficient number, since it is larger than the sum of its proper divisors (23495343).

51689649 is a wasteful number, since it uses less digits than its factorization.

51689649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1566367.

The product of its digits is 466560, while the sum is 48.

The square root of 51689649 is about 7189.5513768246. The cubic root of 51689649 is about 372.5070767240.

The spelling of 51689649 in words is "fifty-one million, six hundred eighty-nine thousand, six hundred forty-nine".