1721095381 has 2 divisors, whose sum is σ = 1721095382. Its totient is φ = 1721095380.

The previous prime is 1721095357. The next prime is 1721095399. The reversal of 1721095381 is 1835901271.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 970883281 + 750212100 = 31159^2 + 27390^2 .

It is an emirp because it is prime and its reverse (1835901271) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1721095381 - 2²³ = 1712706773 is a prime.

It is a super-2 number, since 2×1721095381² = 5924338620999070322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1721095381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1721095301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 860547690 + 860547691.

It is an arithmetic number, because the mean of its divisors is an integer number (860547691).

Almost surely, 2^1721095381 is an apocalyptic number.

It is an amenable number.

1721095381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1721095381 is an equidigital number, since it uses as much as digits as its factorization.

1721095381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 37.

The square root of 1721095381 is about 41486.0865953876. The cubic root of 1721095381 is about 1198.3995750470.

The spelling of 1721095381 in words is "one billion, seven hundred twenty-one million, ninety-five thousand, three hundred eighty-one".