51781822951 has 2 divisors, whose sum is σ = 51781822952. Its totient is φ = 51781822950.

The previous prime is 51781822949. The next prime is 51781822991. The reversal of 51781822951 is 15922818715.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51781822951 - 2¹ = 51781822949 is a prime.

Together with 51781822949, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 51781822895 and 51781822904.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51781822991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25890911475 + 25890911476.

It is an arithmetic number, because the mean of its divisors is an integer number (25890911476).

Almost surely, 2^51781822951 is an apocalyptic number.

51781822951 is a deficient number, since it is larger than the sum of its proper divisors (1).

51781822951 is an equidigital number, since it uses as much as digits as its factorization.

51781822951 is an evil number, because the sum of its binary digits is even.

The product of its digits is 403200, while the sum is 49.

The spelling of 51781822951 in words is "fifty-one billion, seven hundred eighty-one million, eight hundred twenty-two thousand, nine hundred fifty-one".