67172553401981 has 2 divisors, whose sum is σ = 67172553401982. Its totient is φ = 67172553401980.

The previous prime is 67172553401963. The next prime is 67172553402041. The reversal of 67172553401981 is 18910435527176.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55894314062500 + 11278239339481 = 7476250^2 + 3358309^2 .

It is a cyclic number.

It is not a de Polignac number, because 67172553401981 - 2⁴² = 62774506890877 is a prime.

It is a super-2 number, since 2×67172553401981² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 67172553401981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (67172553403981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33586276700990 + 33586276700991.

It is an arithmetic number, because the mean of its divisors is an integer number (33586276700991).

It is a 1-persistent number, because it is pandigital, but 2⋅67172553401981 = 134345106803962 is not.

Almost surely, 2^{67172553401981} is an apocalyptic number.

It is an amenable number.

67172553401981 is a deficient number, since it is larger than the sum of its proper divisors (1).

67172553401981 is an equidigital number, since it uses as much as digits as its factorization.

67172553401981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12700800, while the sum is 59.

The spelling of 67172553401981 in words is "sixty-seven trillion, one hundred seventy-two billion, five hundred fifty-three million, four hundred one thousand, nine hundred eighty-one".