22191000 has 128 divisors (see below), whose sum is σ = 74692800. Its totient is φ = 5452800.

The previous prime is 22190989. The next prime is 22191019. The reversal of 22191000 is 19122.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38716 + ... + 39284.

Almost surely, 2^22191000 is an apocalyptic number.

22191000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22191000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37346400).

22191000 is an abundant number, since it is smaller than the sum of its proper divisors (52501800).

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

22191000 is a wasteful number, since it uses less digits than its factorization.

22191000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 606 (or 592 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 22191000 is about 4710.7324271285. The cubic root of 22191000 is about 281.0124908435.

The spelling of 22191000 in words is "twenty-two million, one hundred ninety-one thousand".