51689357 has 4 divisors (see below), whose sum is σ = 51738780. Its totient is φ = 51639936.

The previous prime is 51689353. The next prime is 51689359. The reversal of 51689357 is 75398615.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75398615 = 5 ⋅15079723.

It can be written as a sum of positive squares in 2 ways, for example, as 11417641 + 40271716 = 3379^2 + 6346^2 .

It is a cyclic number.

It is not a de Polignac number, because 51689357 - 2² = 51689353 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51689353) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23108 + ... + 25245.

It is an arithmetic number, because the mean of its divisors is an integer number (12934695).

Almost surely, 2^51689357 is an apocalyptic number.

It is an amenable number.

51689357 is a deficient number, since it is larger than the sum of its proper divisors (49423).

51689357 is a wasteful number, since it uses less digits than its factorization.

51689357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49422.

The product of its digits is 226800, while the sum is 44.

The square root of 51689357 is about 7189.5310695483. The cubic root of 51689357 is about 372.5063752794.

The spelling of 51689357 in words is "fifty-one million, six hundred eighty-nine thousand, three hundred fifty-seven".