19810061 has 8 divisors (see below), whose sum is σ = 20718720. Its totient is φ = 18905392.

The previous prime is 19810051. The next prime is 19810069. The reversal of 19810061 is 16001891.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19810061 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 19810061.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19810069) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14360 + ... + 15678.

It is an arithmetic number, because the mean of its divisors is an integer number (2589840).

Almost surely, 2^19810061 is an apocalyptic number.

It is an amenable number.

19810061 is a deficient number, since it is larger than the sum of its proper divisors (908659).

19810061 is a wasteful number, since it uses less digits than its factorization.

19810061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1995.

The product of its (nonzero) digits is 432, while the sum is 26.

The square root of 19810061 is about 4450.8494694833. The cubic root of 19810061 is about 270.5797373930.

The spelling of 19810061 in words is "nineteen million, eight hundred ten thousand, sixty-one".