51989657 has 2 divisors, whose sum is σ = 51989658. Its totient is φ = 51989656.

The previous prime is 51989653. The next prime is 51989659. The reversal of 51989657 is 75698915.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 32444416 + 19545241 = 5696^2 + 4421^2 .

It is a cyclic number.

It is not a de Polignac number, because 51989657 - 2² = 51989653 is a prime.

Together with 51989659, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51989653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25994828 + 25994829.

It is an arithmetic number, because the mean of its divisors is an integer number (25994829).

Almost surely, 2^51989657 is an apocalyptic number.

It is an amenable number.

51989657 is a deficient number, since it is larger than the sum of its proper divisors (1).

51989657 is an equidigital number, since it uses as much as digits as its factorization.

51989657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 680400, while the sum is 50.

The square root of 51989657 is about 7210.3853572469. The cubic root of 51989657 is about 373.2263670133.

The spelling of 51989657 in words is "fifty-one million, nine hundred eighty-nine thousand, six hundred fifty-seven".