51542121091 has 2 divisors, whose sum is σ = 51542121092. Its totient is φ = 51542121090.

The previous prime is 51542121089. The next prime is 51542121133. The reversal of 51542121091 is 19012124515.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51542121091 - 2¹ = 51542121089 is a prime.

Together with 51542121089, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (51542121691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25771060545 + 25771060546.

It is an arithmetic number, because the mean of its divisors is an integer number (25771060546).

Almost surely, 2^51542121091 is an apocalyptic number.

51542121091 is a deficient number, since it is larger than the sum of its proper divisors (1).

51542121091 is an equidigital number, since it uses as much as digits as its factorization.

51542121091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3600, while the sum is 31.

The spelling of 51542121091 in words is "fifty-one billion, five hundred forty-two million, one hundred twenty-one thousand, ninety-one".