51555651551 has 2 divisors, whose sum is σ = 51555651552. Its totient is φ = 51555651550.

The previous prime is 51555651509. The next prime is 51555651559. The reversal of 51555651551 is 15515655515.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51555651551 - 2²² = 51551457247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51555651559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25777825775 + 25777825776.

It is an arithmetic number, because the mean of its divisors is an integer number (25777825776).

Almost surely, 2^51555651551 is an apocalyptic number.

51555651551 is a deficient number, since it is larger than the sum of its proper divisors (1).

51555651551 is an equidigital number, since it uses as much as digits as its factorization.

51555651551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 468750, while the sum is 44.

The spelling of 51555651551 in words is "fifty-one billion, five hundred fifty-five million, six hundred fifty-one thousand, five hundred fifty-one".