55140206521 has 2 divisors, whose sum is σ = 55140206522. Its totient is φ = 55140206520.

The previous prime is 55140206431. The next prime is 55140206543. The reversal of 55140206521 is 12560204155.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 33813693225 + 21326513296 = 183885^2 + 146036^2 .

It is a cyclic number.

It is not a de Polignac number, because 55140206521 - 2⁷ = 55140206393 is a prime.

It is not a weakly prime, because it can be changed into another prime (55140206591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27570103260 + 27570103261.

It is an arithmetic number, because the mean of its divisors is an integer number (27570103261).

Almost surely, 2^55140206521 is an apocalyptic number.

It is an amenable number.

55140206521 is a deficient number, since it is larger than the sum of its proper divisors (1).

55140206521 is an equidigital number, since it uses as much as digits as its factorization.

55140206521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12000, while the sum is 31.

The spelling of 55140206521 in words is "fifty-five billion, one hundred forty million, two hundred six thousand, five hundred twenty-one".