21851034 has 16 divisors (see below), whose sum is σ = 43804800. Its totient is φ = 7266560.

The previous prime is 21851033. The next prime is 21851041. The reversal of 21851034 is 43015812.

It is a junction number, because it is equal to n+sod(n) for n = 21850995 and 21851013.

It is not an unprimeable number, because it can be changed into a prime (21851033) 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, 1362 + ... + 6749.

It is an arithmetic number, because the mean of its divisors is an integer number (2737800).

Almost surely, 2^21851034 is an apocalyptic number.

21851034 is an abundant number, since it is smaller than the sum of its proper divisors (21953766).

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

21851034 is a wasteful number, since it uses less digits than its factorization.

21851034 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8565.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 21851034 is about 4674.5089581688. The cubic root of 21851034 is about 279.5700629632.

Adding to 21851034 its reverse (43015812), we get a palindrome (64866846).

The spelling of 21851034 in words is "twenty-one million, eight hundred fifty-one thousand, thirty-four".