166000631001421 has 2 divisors, whose sum is σ = 166000631001422. Its totient is φ = 166000631001420.

The previous prime is 166000631001383. The next prime is 166000631001437. The reversal of 166000631001421 is 124100136000661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 83584392002500 + 82416238998921 = 9142450^2 + 9078339^2 .

It is a cyclic number.

It is not a de Polignac number, because 166000631001421 - 2¹³ = 166000630993229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166000631001461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83000315500710 + 83000315500711.

It is an arithmetic number, because the mean of its divisors is an integer number (83000315500711).

Almost surely, 2^{166000631001421} is an apocalyptic number.

It is an amenable number.

166000631001421 is a deficient number, since it is larger than the sum of its proper divisors (1).

166000631001421 is an equidigital number, since it uses as much as digits as its factorization.

166000631001421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 31.

The spelling of 166000631001421 in words is "one hundred sixty-six trillion, six hundred thirty-one million, one thousand, four hundred twenty-one".