1881540217 has 2 divisors, whose sum is σ = 1881540218. Its totient is φ = 1881540216.

The previous prime is 1881540203. The next prime is 1881540223. The reversal of 1881540217 is 7120451881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1864598761 + 16941456 = 43181^2 + 4116^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1881540217 is a prime.

It is a super-3 number, since 3×1881540217³ (a number of 29 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (1881540517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 940770108 + 940770109.

It is an arithmetic number, because the mean of its divisors is an integer number (940770109).

Almost surely, 2^1881540217 is an apocalyptic number.

It is an amenable number.

1881540217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1881540217 is an equidigital number, since it uses as much as digits as its factorization.

1881540217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17920, while the sum is 37.

The square root of 1881540217 is about 43376.7243691821. The cubic root of 1881540217 is about 1234.5381122288.

The spelling of 1881540217 in words is "one billion, eight hundred eighty-one million, five hundred forty thousand, two hundred seventeen".