51781603 has 2 divisors, whose sum is σ = 51781604. Its totient is φ = 51781602.

The previous prime is 51781571. The next prime is 51781621. The reversal of 51781603 is 30618715.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51781603 - 2⁵ = 51781571 is a prime.

It is not a weakly prime, because it can be changed into another prime (51781673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25890801 + 25890802.

It is an arithmetic number, because the mean of its divisors is an integer number (25890802).

Almost surely, 2^51781603 is an apocalyptic number.

51781603 is a deficient number, since it is larger than the sum of its proper divisors (1).

51781603 is an equidigital number, since it uses as much as digits as its factorization.

51781603 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 51781603 is about 7195.9435100618. The cubic root of 51781603 is about 372.7278380339.

The spelling of 51781603 in words is "fifty-one million, seven hundred eighty-one thousand, six hundred three".