21870150 has 48 divisors (see below), whose sum is σ = 54573888. Its totient is φ = 5796000.

The previous prime is 21870131. The next prime is 21870161. The reversal of 21870150 is 5107812.

It is a super-2 number, since 2×21870150² = 956606922045000, 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 21870150.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31305 + ... + 31995.

It is an arithmetic number, because the mean of its divisors is an integer number (1136956).

Almost surely, 2^21870150 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21870150, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27286944).

21870150 is an abundant number, since it is smaller than the sum of its proper divisors (32703738).

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

21870150 is a wasteful number, since it uses less digits than its factorization.

21870150 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 917 (or 912 counting only the distinct ones).

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

The square root of 21870150 is about 4676.5532179159. The cubic root of 21870150 is about 279.6515648826.

Adding to 21870150 its reverse (5107812), we get a palindrome (26977962).

The spelling of 21870150 in words is "twenty-one million, eight hundred seventy thousand, one hundred fifty".