21989110 has 32 divisors (see below), whose sum is σ = 46503072. Its totient is φ = 7380480.

The previous prime is 21989101. The next prime is 21989111. The reversal of 21989110 is 1198912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21989111) 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, 6259 + ... + 9118.

It is an arithmetic number, because the mean of its divisors is an integer number (1453221).

Almost surely, 2^21989110 is an apocalyptic number.

21989110 is an abundant number, since it is smaller than the sum of its proper divisors (24513962).

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

21989110 is a wasteful number, since it uses less digits than its factorization.

21989110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15408.

The product of its (nonzero) digits is 1296, while the sum is 31.

The square root of 21989110 is about 4689.2547382287. The cubic root of 21989110 is about 280.1576917859.

The spelling of 21989110 in words is "twenty-one million, nine hundred eighty-nine thousand, one hundred ten".