3438987781 has 2 divisors, whose sum is σ = 3438987782. Its totient is φ = 3438987780.

The previous prime is 3438987779. The next prime is 3438987847. The reversal of 3438987781 is 1877898343.

3438987781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3438766881 + 220900 = 58641^2 + 470^2 .

It is an emirp because it is prime and its reverse (1877898343) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3438987781 - 2¹ = 3438987779 is a prime.

It is a super-2 number, since 2×3438987781² = 23653273915734607922, which contains 22 as substring.

Together with 3438987779, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3438987731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1719493890 + 1719493891.

It is an arithmetic number, because the mean of its divisors is an integer number (1719493891).

Almost surely, 2^3438987781 is an apocalyptic number.

It is an amenable number.

3438987781 is a deficient number, since it is larger than the sum of its proper divisors (1).

3438987781 is an equidigital number, since it uses as much as digits as its factorization.

3438987781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8128512, while the sum is 58.

The square root of 3438987781 is about 58642.8834642363. The cubic root of 3438987781 is about 1509.4203849722.

The spelling of 3438987781 in words is "three billion, four hundred thirty-eight million, nine hundred eighty-seven thousand, seven hundred eighty-one".