911667138821 has 2 divisors, whose sum is σ = 911667138822. Its totient is φ = 911667138820.

The previous prime is 911667138803. The next prime is 911667138841. The reversal of 911667138821 is 128831766119.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 531311245921 + 380355892900 = 728911^2 + 616730^2 .

It is a cyclic number.

It is not a de Polignac number, because 911667138821 - 2³⁸ = 636789231877 is a prime.

It is a super-2 number, since 2×911667138821² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (911667138841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 455833569410 + 455833569411.

It is an arithmetic number, because the mean of its divisors is an integer number (455833569411).

Almost surely, 2^911667138821 is an apocalyptic number.

It is an amenable number.

911667138821 is a deficient number, since it is larger than the sum of its proper divisors (1).

911667138821 is an equidigital number, since it uses as much as digits as its factorization.

911667138821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 870912, while the sum is 53.

The spelling of 911667138821 in words is "nine hundred eleven billion, six hundred sixty-seven million, one hundred thirty-eight thousand, eight hundred twenty-one".