51455157991 has 2 divisors, whose sum is σ = 51455157992. Its totient is φ = 51455157990.

The previous prime is 51455157937. The next prime is 51455158031. The reversal of 51455157991 is 19975155415.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51455157991 - 2²¹ = 51453060839 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51455157911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25727578995 + 25727578996.

It is an arithmetic number, because the mean of its divisors is an integer number (25727578996).

Almost surely, 2^51455157991 is an apocalyptic number.

51455157991 is a deficient number, since it is larger than the sum of its proper divisors (1).

51455157991 is an equidigital number, since it uses as much as digits as its factorization.

51455157991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1417500, while the sum is 52.

The spelling of 51455157991 in words is "fifty-one billion, four hundred fifty-five million, one hundred fifty-seven thousand, nine hundred ninety-one".