1001781493 has 2 divisors, whose sum is σ = 1001781494. Its totient is φ = 1001781492.

The previous prime is 1001781437. The next prime is 1001781503. The reversal of 1001781493 is 3941871001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 999950884 + 1830609 = 31622^2 + 1353^2 .

It is an emirp because it is prime and its reverse (3941871001) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1001781493 - 2²¹ = 999684341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1001781433) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500890746 + 500890747.

It is an arithmetic number, because the mean of its divisors is an integer number (500890747).

Almost surely, 2^1001781493 is an apocalyptic number.

It is an amenable number.

1001781493 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001781493 is an equidigital number, since it uses as much as digits as its factorization.

1001781493 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 1001781493 is about 31650.9319452050. The cubic root of 1001781493 is about 1000.5934787133.

The spelling of 1001781493 in words is "one billion, one million, seven hundred eighty-one thousand, four hundred ninety-three".