55206542621 has 2 divisors, whose sum is σ = 55206542622. Its totient is φ = 55206542620.

The previous prime is 55206542609. The next prime is 55206542707. The reversal of 55206542621 is 12624560255.

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., 49673265625 + 5533276996 = 222875^2 + 74386^2 .

It is a cyclic number.

It is not a de Polignac number, because 55206542621 - 2¹⁴ = 55206526237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55206542021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27603271310 + 27603271311.

It is an arithmetic number, because the mean of its divisors is an integer number (27603271311).

Almost surely, 2^55206542621 is an apocalyptic number.

It is an amenable number.

55206542621 is a deficient number, since it is larger than the sum of its proper divisors (1).

55206542621 is an equidigital number, since it uses as much as digits as its factorization.

55206542621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144000, while the sum is 38.

The spelling of 55206542621 in words is "fifty-five billion, two hundred six million, five hundred forty-two thousand, six hundred twenty-one".