21807150 has 24 divisors (see below), whose sum is σ = 54082104. Its totient is φ = 5815200.

The previous prime is 21807133. The next prime is 21807157. The reversal of 21807150 is 5170812.

It is a super-2 number, since 2×21807150² = 951103582245000, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21807150.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21807157) 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, 72541 + ... + 72840.

It is an arithmetic number, because the mean of its divisors is an integer number (2253421).

Almost surely, 2^21807150 is an apocalyptic number.

21807150 is an abundant number, since it is smaller than the sum of its proper divisors (32274954).

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

21807150 is a wasteful number, since it uses less digits than its factorization.

21807150 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145396 (or 145391 counting only the distinct ones).

The product of its (nonzero) digits is 560, while the sum is 24.

The square root of 21807150 is about 4669.8126300741. The cubic root of 21807150 is about 279.3827815899.

Adding to 21807150 its reverse (5170812), we get a palindrome (26977962).

The spelling of 21807150 in words is "twenty-one million, eight hundred seven thousand, one hundred fifty".