21954489 has 8 divisors (see below), whose sum is σ = 30545472. Its totient is φ = 13999920.

The previous prime is 21954487. The next prime is 21954511. The reversal of 21954489 is 98445912.

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

It is not a de Polignac number, because 21954489 - 2¹ = 21954487 is a prime.

It is a super-2 number, since 2×21954489² = 963999174502242, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21954489.

It is not an unprimeable number, because it can be changed into a prime (21954487) 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, 159022 + ... + 159159.

It is an arithmetic number, because the mean of its divisors is an integer number (3818184).

Almost surely, 2^21954489 is an apocalyptic number.

It is an amenable number.

21954489 is a deficient number, since it is larger than the sum of its proper divisors (8590983).

21954489 is a wasteful number, since it uses less digits than its factorization.

21954489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 318207.

The product of its digits is 103680, while the sum is 42.

The square root of 21954489 is about 4685.5617592771. The cubic root of 21954489 is about 280.0105820831.

The spelling of 21954489 in words is "twenty-one million, nine hundred fifty-four thousand, four hundred eighty-nine".