19868890 has 8 divisors (see below), whose sum is σ = 35764020. Its totient is φ = 7947552.

The previous prime is 19868879. The next prime is 19868897. The reversal of 19868890 is 9886891.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 18258529 + 1610361 = 4273^2 + 1269^2 .

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

It is not an unprimeable number, because it can be changed into a prime (19868897) 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, 993435 + ... + 993454.

Almost surely, 2^19868890 is an apocalyptic number.

19868890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19868890 is a deficient number, since it is larger than the sum of its proper divisors (15895130).

19868890 is a wasteful number, since it uses less digits than its factorization.

19868890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1986896.

The product of its (nonzero) digits is 248832, while the sum is 49.

The square root of 19868890 is about 4457.4533087852. The cubic root of 19868890 is about 270.8473153071.

The spelling of 19868890 in words is "nineteen million, eight hundred sixty-eight thousand, eight hundred ninety".