21851150 has 24 divisors (see below), whose sum is σ = 42412464. Its totient is φ = 8360000.

The previous prime is 21851119. The next prime is 21851153. The reversal of 21851150 is 5115812.

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21851153) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8351 + ... + 10650.

It is an arithmetic number, because the mean of its divisors is an integer number (1767186).

Almost surely, 2^21851150 is an apocalyptic number.

21851150 is a deficient number, since it is larger than the sum of its proper divisors (20561314).

21851150 is a wasteful number, since it uses less digits than its factorization.

21851150 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19036 (or 19031 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 23.

The square root of 21851150 is about 4674.5213658727. The cubic root of 21851150 is about 279.5705576777.

Adding to 21851150 its reverse (5115812), we get a palindrome (26966962).

The spelling of 21851150 in words is "twenty-one million, eight hundred fifty-one thousand, one hundred fifty".