3638634531811 has 2 divisors, whose sum is σ = 3638634531812. Its totient is φ = 3638634531810.

The previous prime is 3638634531793. The next prime is 3638634531839. The reversal of 3638634531811 is 1181354368363.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3638634531811 - 2⁷ = 3638634531683 is a prime.

It is a super-2 number, since 2×3638634531811² (a number of 26 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (3638634531841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1819317265905 + 1819317265906.

It is an arithmetic number, because the mean of its divisors is an integer number (1819317265906).

Almost surely, 2^{3638634531811} is an apocalyptic number.

3638634531811 is a deficient number, since it is larger than the sum of its proper divisors (1).

3638634531811 is an equidigital number, since it uses as much as digits as its factorization.

3638634531811 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3732480, while the sum is 52.

The spelling of 3638634531811 in words is "three trillion, six hundred thirty-eight billion, six hundred thirty-four million, five hundred thirty-one thousand, eight hundred eleven".