67571604994921 has 2 divisors, whose sum is σ = 67571604994922. Its totient is φ = 67571604994920.

The previous prime is 67571604994871. The next prime is 67571604994931. The reversal of 67571604994921 is 12949940617576.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47940183493225 + 19631421501696 = 6923885^2 + 4430736^2 .

It is a cyclic number.

It is not a de Polignac number, because 67571604994921 - 2¹¹ = 67571604992873 is a prime.

It is not a weakly prime, because it can be changed into another prime (67571604994931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33785802497460 + 33785802497461.

It is an arithmetic number, because the mean of its divisors is an integer number (33785802497461).

Almost surely, 2^{67571604994921} is an apocalyptic number.

It is an amenable number.

67571604994921 is a deficient number, since it is larger than the sum of its proper divisors (1).

67571604994921 is an equidigital number, since it uses as much as digits as its factorization.

67571604994921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 205752960, while the sum is 70.

The spelling of 67571604994921 in words is "sixty-seven trillion, five hundred seventy-one billion, six hundred four million, nine hundred ninety-four thousand, nine hundred twenty-one".