16851668501 has 2 divisors, whose sum is σ = 16851668502. Its totient is φ = 16851668500.

The previous prime is 16851668473. The next prime is 16851668539. The reversal of 16851668501 is 10586615861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12583006276 + 4268662225 = 112174^2 + 65335^2 .

It is a cyclic number.

It is not a de Polignac number, because 16851668501 - 2⁶ = 16851668437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16851661501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8425834250 + 8425834251.

It is an arithmetic number, because the mean of its divisors is an integer number (8425834251).

Almost surely, 2^16851668501 is an apocalyptic number.

It is an amenable number.

16851668501 is a deficient number, since it is larger than the sum of its proper divisors (1).

16851668501 is an equidigital number, since it uses as much as digits as its factorization.

16851668501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 345600, while the sum is 47.

The spelling of 16851668501 in words is "sixteen billion, eight hundred fifty-one million, six hundred sixty-eight thousand, five hundred one".