13551755821 has 2 divisors, whose sum is σ = 13551755822. Its totient is φ = 13551755820.

The previous prime is 13551755797. The next prime is 13551755863. The reversal of 13551755821 is 12855715531.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12523848100 + 1027907721 = 111910^2 + 32061^2 .

It is a cyclic number.

It is not a de Polignac number, because 13551755821 - 2²⁷ = 13417538093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13551755891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6775877910 + 6775877911.

It is an arithmetic number, because the mean of its divisors is an integer number (6775877911).

Almost surely, 2^13551755821 is an apocalyptic number.

It is an amenable number.

13551755821 is a deficient number, since it is larger than the sum of its proper divisors (1).

13551755821 is an equidigital number, since it uses as much as digits as its factorization.

13551755821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 210000, while the sum is 43.

The spelling of 13551755821 in words is "thirteen billion, five hundred fifty-one million, seven hundred fifty-five thousand, eight hundred twenty-one".