21741858 has 40 divisors (see below), whose sum is σ = 49228608. Its totient is φ = 7171416.

The previous prime is 21741847. The next prime is 21741869. The reversal of 21741858 is 85814712.

It is an interprime number because it is at equal distance from previous prime (21741847) and next prime (21741869).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 16035 + ... + 17337.

Almost surely, 2^21741858 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21741858, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24614304).

21741858 is an abundant number, since it is smaller than the sum of its proper divisors (27486750).

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

21741858 is a wasteful number, since it uses less digits than its factorization.

21741858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1420 (or 1411 counting only the distinct ones).

The product of its digits is 17920, while the sum is 36.

The square root of 21741858 is about 4662.8165308105. The cubic root of 21741858 is about 279.1036728834.

The spelling of 21741858 in words is "twenty-one million, seven hundred forty-one thousand, eight hundred fifty-eight".