215366145437881 has 2 divisors, whose sum is σ = 215366145437882. Its totient is φ = 215366145437880.

The previous prime is 215366145437843. The next prime is 215366145437897. The reversal of 215366145437881 is 188734541663512.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 177264167055481 + 38101978382400 = 13314059^2 + 6172680^2 .

It is a cyclic number.

It is not a de Polignac number, because 215366145437881 - 2⁷ = 215366145437753 is a prime.

It is a super-2 number, since 2×215366145437881² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (215366145438881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107683072718940 + 107683072718941.

It is an arithmetic number, because the mean of its divisors is an integer number (107683072718941).

Almost surely, 2^{215366145437881} is an apocalyptic number.

It is an amenable number.

215366145437881 is a deficient number, since it is larger than the sum of its proper divisors (1).

215366145437881 is an equidigital number, since it uses as much as digits as its factorization.

215366145437881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 116121600, while the sum is 64.

The spelling of 215366145437881 in words is "two hundred fifteen trillion, three hundred sixty-six billion, one hundred forty-five million, four hundred thirty-seven thousand, eight hundred eighty-one".