34639731781 has 2 divisors, whose sum is σ = 34639731782. Its totient is φ = 34639731780.

The previous prime is 34639731719. The next prime is 34639731799. The reversal of 34639731781 is 18713793643.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23867160100 + 10772571681 = 154490^2 + 103791^2 .

It is an emirp because it is prime and its reverse (18713793643) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 34639731781 - 2⁷ = 34639731653 is a prime.

It is a super-2 number, since 2×34639731781² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (34639731701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17319865890 + 17319865891.

It is an arithmetic number, because the mean of its divisors is an integer number (17319865891).

Almost surely, 2^34639731781 is an apocalyptic number.

It is an amenable number.

34639731781 is a deficient number, since it is larger than the sum of its proper divisors (1).

34639731781 is an equidigital number, since it uses as much as digits as its factorization.

34639731781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2286144, while the sum is 52.

The spelling of 34639731781 in words is "thirty-four billion, six hundred thirty-nine million, seven hundred thirty-one thousand, seven hundred eighty-one".