19447989 has 16 divisors (see below), whose sum is σ = 28892160. Its totient is φ = 11534960.

The previous prime is 19447973. The next prime is 19447991. The reversal of 19447989 is 98974491.

It is a cyclic number.

It is not a de Polignac number, because 19447989 - 2⁴ = 19447973 is a prime.

It is a super-2 number, since 2×19447989² = 756448552288242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19447919) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4719 + ... + 7820.

It is an arithmetic number, because the mean of its divisors is an integer number (1805760).

Almost surely, 2^19447989 is an apocalyptic number.

It is an amenable number.

19447989 is a deficient number, since it is larger than the sum of its proper divisors (9444171).

19447989 is a wasteful number, since it uses less digits than its factorization.

19447989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12600.

The product of its digits is 653184, while the sum is 51.

The square root of 19447989 is about 4409.9874149480. The cubic root of 19447989 is about 268.9211130232.

The spelling of 19447989 in words is "nineteen million, four hundred forty-seven thousand, nine hundred eighty-nine".