21911190 has 64 divisors (see below), whose sum is σ = 60742656. Its totient is φ = 4954752.

The previous prime is 21911167. The next prime is 21911213. The reversal of 21911190 is 9111912.

It is an interprime number because it is at equal distance from previous prime (21911167) and next prime (21911213).

It is a super-2 number, since 2×21911190² = 960200494432200, 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 21911190.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21124 + ... + 22136.

It is an arithmetic number, because the mean of its divisors is an integer number (949104).

Almost surely, 2^21911190 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21911190, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30371328).

21911190 is an abundant number, since it is smaller than the sum of its proper divisors (38831466).

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

21911190 is a wasteful number, since it uses less digits than its factorization.

21911190 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1133.

The product of its (nonzero) digits is 162, while the sum is 24.

The square root of 21911190 is about 4680.9390083615. The cubic root of 21911190 is about 279.8263804613.

The spelling of 21911190 in words is "twenty-one million, nine hundred eleven thousand, one hundred ninety".