51677771987 has 2 divisors, whose sum is σ = 51677771988. Its totient is φ = 51677771986.

The previous prime is 51677771969. The next prime is 51677771989. The reversal of 51677771987 is 78917777615.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51677771987 is a prime.

Together with 51677771989, 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 (51677771989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25838885993 + 25838885994.

It is an arithmetic number, because the mean of its divisors is an integer number (25838885994).

Almost surely, 2^51677771987 is an apocalyptic number.

51677771987 is a deficient number, since it is larger than the sum of its proper divisors (1).

51677771987 is an equidigital number, since it uses as much as digits as its factorization.

51677771987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36303120, while the sum is 65.

The spelling of 51677771987 in words is "fifty-one billion, six hundred seventy-seven million, seven hundred seventy-one thousand, nine hundred eighty-seven".