21481234 has 16 divisors (see below), whose sum is σ = 34214400. Its totient is φ = 10080064.

The previous prime is 21481231. The next prime is 21481259. The reversal of 21481234 is 43218412.

It is a super-2 number, since 2×21481234² = 922886828325512, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21481199 and 21481208.

It is not an unprimeable number, because it can be changed into a prime (21481231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15627 + ... + 16945.

It is an arithmetic number, because the mean of its divisors is an integer number (2138400).

Almost surely, 2^21481234 is an apocalyptic number.

21481234 is a deficient number, since it is larger than the sum of its proper divisors (12733166).

21481234 is a wasteful number, since it uses less digits than its factorization.

21481234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1817.

The product of its digits is 1536, while the sum is 25.

The square root of 21481234 is about 4634.7852161670. The cubic root of 21481234 is about 277.9839629829.

Adding to 21481234 its reverse (43218412), we get a palindrome (64699646).

The spelling of 21481234 in words is "twenty-one million, four hundred eighty-one thousand, two hundred thirty-four".