21989046 has 8 divisors (see below), whose sum is σ = 43978104. Its totient is φ = 7329680.

The previous prime is 21989029. The next prime is 21989053. The reversal of 21989046 is 64098912.

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

21989046 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 21988995 and 21989013.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1832415 + ... + 1832426.

It is an arithmetic number, because the mean of its divisors is an integer number (5497263).

Almost surely, 2^21989046 is an apocalyptic number.

21989046 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21989046 is a wasteful number, since it uses less digits than its factorization.

21989046 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3664846.

The product of its (nonzero) digits is 31104, while the sum is 39.

The square root of 21989046 is about 4689.2479141116. The cubic root of 21989046 is about 280.1574199831.

The spelling of 21989046 in words is "twenty-one million, nine hundred eighty-nine thousand, forty-six".