21310534 has 16 divisors (see below), whose sum is σ = 37792800. Its totient is φ = 8817984.

The previous prime is 21310519. The next prime is 21310561. The reversal of 21310534 is 43501312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25839 + ... + 26650.

It is an arithmetic number, because the mean of its divisors is an integer number (2362050).

Almost surely, 2^21310534 is an apocalyptic number.

21310534 is a deficient number, since it is larger than the sum of its proper divisors (16482266).

21310534 is a wasteful number, since it uses less digits than its factorization.

21310534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52527.

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 21310534 is about 4616.3333935061. Note that the first 4 decimals coincide. The cubic root of 21310534 is about 277.2456734299.

Adding to 21310534 its reverse (43501312), we get a palindrome (64811846).

The spelling of 21310534 in words is "twenty-one million, three hundred ten thousand, five hundred thirty-four".