16555220321357 has 2 divisors, whose sum is σ = 16555220321358. Its totient is φ = 16555220321356.

The previous prime is 16555220321303. The next prime is 16555220321363. The reversal of 16555220321357 is 75312302255561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13674752847721 + 2880467473636 = 3697939^2 + 1697194^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16555220321357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16555220321657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8277610160678 + 8277610160679.

It is an arithmetic number, because the mean of its divisors is an integer number (8277610160679).

Almost surely, 2^{16555220321357} is an apocalyptic number.

It is an amenable number.

16555220321357 is a deficient number, since it is larger than the sum of its proper divisors (1).

16555220321357 is an equidigital number, since it uses as much as digits as its factorization.

16555220321357 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1890000, while the sum is 47.

The spelling of 16555220321357 in words is "sixteen trillion, five hundred fifty-five billion, two hundred twenty million, three hundred twenty-one thousand, three hundred fifty-seven".