19904889 has 16 divisors (see below), whose sum is σ = 27267840. Its totient is φ = 12910800.

The previous prime is 19904881. The next prime is 19904891. The reversal of 19904889 is 98840991.

It is not a de Polignac number, because 19904889 - 2³ = 19904881 is a prime.

It is a super-2 number, since 2×19904889² = 792409212204642, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19904881) 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, 18414 + ... + 19464.

It is an arithmetic number, because the mean of its divisors is an integer number (1704240).

Almost surely, 2^19904889 is an apocalyptic number.

It is an amenable number.

19904889 is a deficient number, since it is larger than the sum of its proper divisors (7362951).

19904889 is a wasteful number, since it uses less digits than its factorization.

19904889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1220.

The product of its (nonzero) digits is 186624, while the sum is 48.

The square root of 19904889 is about 4461.4895494666. The cubic root of 19904889 is about 271.0107928146.

The spelling of 19904889 in words is "nineteen million, nine hundred four thousand, eight hundred eighty-nine".