21492889 has 8 divisors (see below), whose sum is σ = 24203520. Its totient is φ = 18908400.

The previous prime is 21492883. The next prime is 21492937. The reversal of 21492889 is 98829412.

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

It is a cyclic number.

It is not a de Polignac number, because 21492889 - 2³ = 21492881 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21492881) 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, 31174 + ... + 31855.

It is an arithmetic number, because the mean of its divisors is an integer number (3025440).

Almost surely, 2^21492889 is an apocalyptic number.

It is an amenable number.

21492889 is a deficient number, since it is larger than the sum of its proper divisors (2710631).

21492889 is a wasteful number, since it uses less digits than its factorization.

21492889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63071.

The product of its digits is 82944, while the sum is 43.

The square root of 21492889 is about 4636.0423854835. The cubic root of 21492889 is about 278.0342288306.

The spelling of 21492889 in words is "twenty-one million, four hundred ninety-two thousand, eight hundred eighty-nine".