21834881 has 6 divisors (see below), whose sum is σ = 22562946. Its totient is φ = 21129600.

The previous prime is 21834871. The next prime is 21834899. The reversal of 21834881 is 18843812.

It can be written as a sum of positive squares in only one way, i.e., 17774656 + 4060225 = 4216^2 + 2015^2 .

It is not a de Polignac number, because 21834881 - 2¹⁰ = 21833857 is a prime.

It is a super-2 number, since 2×21834881² = 953524056568322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21834821) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10400 + ... + 12321.

It is an arithmetic number, because the mean of its divisors is an integer number (3760491).

Almost surely, 2^21834881 is an apocalyptic number.

It is an amenable number.

21834881 is a deficient number, since it is larger than the sum of its proper divisors (728065).

21834881 is an equidigital number, since it uses as much as digits as its factorization.

21834881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22783 (or 22752 counting only the distinct ones).

The product of its digits is 12288, while the sum is 35.

The square root of 21834881 is about 4672.7808636828. The cubic root of 21834881 is about 279.5011568655.

The spelling of 21834881 in words is "twenty-one million, eight hundred thirty-four thousand, eight hundred eighty-one".