55221378097 has 2 divisors, whose sum is σ = 55221378098. Its totient is φ = 55221378096.

The previous prime is 55221378059. The next prime is 55221378131. The reversal of 55221378097 is 79087312255.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53066190321 + 2155187776 = 230361^2 + 46424^2 .

It is a cyclic number.

It is not a de Polignac number, because 55221378097 - 2²⁷ = 55087160369 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 55221378097.

It is not a weakly prime, because it can be changed into another prime (55221379097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27610689048 + 27610689049.

It is an arithmetic number, because the mean of its divisors is an integer number (27610689049).

Almost surely, 2^55221378097 is an apocalyptic number.

It is an amenable number.

55221378097 is a deficient number, since it is larger than the sum of its proper divisors (1).

55221378097 is an equidigital number, since it uses as much as digits as its factorization.

55221378097 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1058400, while the sum is 49.

The spelling of 55221378097 in words is "fifty-five billion, two hundred twenty-one million, three hundred seventy-eight thousand, ninety-seven".