19490081 has 4 divisors (see below), whose sum is σ = 20989332. Its totient is φ = 17990832.

The previous prime is 19490063. The next prime is 19490087. The reversal of 19490081 is 18009491.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5837056 + 13653025 = 2416^2 + 3695^2 .

It is a cyclic number.

It is not a de Polignac number, because 19490081 - 2¹⁴ = 19473697 is a prime.

It is a super-2 number, since 2×19490081² = 759726514773122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19490087) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 749606 + ... + 749631.

It is an arithmetic number, because the mean of its divisors is an integer number (5247333).

Almost surely, 2^19490081 is an apocalyptic number.

It is an amenable number.

19490081 is a deficient number, since it is larger than the sum of its proper divisors (1499251).

19490081 is a wasteful number, since it uses less digits than its factorization.

19490081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1499250.

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 19490081 is about 4414.7571847158. The cubic root of 19490081 is about 269.1149851838.

The spelling of 19490081 in words is "nineteen million, four hundred ninety thousand, eighty-one".