21109374 has 96 divisors (see below), whose sum is σ = 55036800. Its totient is φ = 5762880.

The previous prime is 21109369. The next prime is 21109381. The reversal of 21109374 is 47390112.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 151797 + ... + 151935.

It is an arithmetic number, because the mean of its divisors is an integer number (573300).

It is a vampire number, since it can be written as 2301 ⋅ 9174 (with its own digits).

Almost surely, 2^21109374 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21109374, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27518400).

21109374 is an abundant number, since it is smaller than the sum of its proper divisors (33927426).

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

21109374 is a wasteful number, since it uses less digits than its factorization.

With its successor (21109375) it forms a Ruth-Aaron pair, since the sum of their prime factors is the same (230).

21109374 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230 (or 227 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 21109374 is about 4594.4938785464. The cubic root of 21109374 is about 276.3705640012.

Adding to 21109374 its reverse (47390112), we get a palindrome (68499486).

The spelling of 21109374 in words is "twenty-one million, one hundred nine thousand, three hundred seventy-four".