218179281801557 has 2 divisors, whose sum is σ = 218179281801558. Its totient is φ = 218179281801556.

The previous prime is 218179281801539. The next prime is 218179281801653. The reversal of 218179281801557 is 755108182971812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 217878441618436 + 300840183121 = 14760706^2 + 548489^2 .

It is a cyclic number.

It is not a de Polignac number, because 218179281801557 - 2¹² = 218179281797461 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 218179281801493 and 218179281801502.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218179281101557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109089640900778 + 109089640900779.

It is an arithmetic number, because the mean of its divisors is an integer number (109089640900779).

Almost surely, 2^{218179281801557} is an apocalyptic number.

It is an amenable number.

218179281801557 is a deficient number, since it is larger than the sum of its proper divisors (1).

218179281801557 is an equidigital number, since it uses as much as digits as its factorization.

218179281801557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22579200, while the sum is 65.

The spelling of 218179281801557 in words is "two hundred eighteen trillion, one hundred seventy-nine billion, two hundred eighty-one million, eight hundred one thousand, five hundred fifty-seven".