55451998081 has 2 divisors, whose sum is σ = 55451998082. Its totient is φ = 55451998080.

The previous prime is 55451998079. The next prime is 55451998103. The reversal of 55451998081 is 18089915455.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35276352400 + 20175645681 = 187820^2 + 142041^2 .

It is a cyclic number.

It is not a de Polignac number, because 55451998081 - 2¹ = 55451998079 is a prime.

It is a super-2 number, since 2×55451998081² (a number of 22 digits) contains 22 as substring.

Together with 55451998079, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (55451998001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27725999040 + 27725999041.

It is an arithmetic number, because the mean of its divisors is an integer number (27725999041).

Almost surely, 2^55451998081 is an apocalyptic number.

It is an amenable number.

55451998081 is a deficient number, since it is larger than the sum of its proper divisors (1).

55451998081 is an equidigital number, since it uses as much as digits as its factorization.

55451998081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592000, while the sum is 55.

The spelling of 55451998081 in words is "fifty-five billion, four hundred fifty-one million, nine hundred ninety-eight thousand, eighty-one".