19890061 has 2 divisors, whose sum is σ = 19890062. Its totient is φ = 19890060.

The previous prime is 19890049. The next prime is 19890083. The reversal of 19890061 is 16009891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18404100 + 1485961 = 4290^2 + 1219^2 .

It is a cyclic number.

It is not a de Polignac number, because 19890061 - 2⁵ = 19890029 is a prime.

It is a super-2 number, since 2×19890061² = 791229053167442, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 19889999 and 19890026.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19890161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9945030 + 9945031.

It is an arithmetic number, because the mean of its divisors is an integer number (9945031).

Almost surely, 2^19890061 is an apocalyptic number.

It is an amenable number.

19890061 is a deficient number, since it is larger than the sum of its proper divisors (1).

19890061 is an equidigital number, since it uses as much as digits as its factorization.

19890061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 19890061 is about 4459.8274630304. The cubic root of 19890061 is about 270.9434802679.

The spelling of 19890061 in words is "nineteen million, eight hundred ninety thousand, sixty-one".