16621421806141 has 2 divisors, whose sum is σ = 16621421806142. Its totient is φ = 16621421806140.

The previous prime is 16621421806079. The next prime is 16621421806147. The reversal of 16621421806141 is 14160812412661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15957108783225 + 664313022916 = 3994635^2 + 815054^2 .

It is a cyclic number.

It is not a de Polignac number, because 16621421806141 - 2¹¹ = 16621421804093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16621421806147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8310710903070 + 8310710903071.

It is an arithmetic number, because the mean of its divisors is an integer number (8310710903071).

Almost surely, 2^{16621421806141} is an apocalyptic number.

It is an amenable number.

16621421806141 is a deficient number, since it is larger than the sum of its proper divisors (1).

16621421806141 is an equidigital number, since it uses as much as digits as its factorization.

16621421806141 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 110592, while the sum is 43.

The spelling of 16621421806141 in words is "sixteen trillion, six hundred twenty-one billion, four hundred twenty-one million, eight hundred six thousand, one hundred forty-one".