21012150 has 48 divisors (see below), whose sum is σ = 52568064. Its totient is φ = 5554080.

The previous prime is 21012137. The next prime is 21012151. The reversal of 21012150 is 5121012.

It is a super-3 number, since 3×21012150³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012151) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18499 + ... + 19601.

It is an arithmetic number, because the mean of its divisors is an integer number (1095168).

Almost surely, 2^21012150 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21012150, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26284032).

21012150 is an abundant number, since it is smaller than the sum of its proper divisors (31555914).

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

21012150 is a wasteful number, since it uses less digits than its factorization.

21012150 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1245 (or 1240 counting only the distinct ones).

The product of its (nonzero) digits is 20, while the sum is 12.

The square root of 21012150 is about 4583.9011769452. The cubic root of 21012150 is about 275.9456152033.

Adding to 21012150 its reverse (5121012), we get a palindrome (26133162).

The spelling of 21012150 in words is "twenty-one million, twelve thousand, one hundred fifty".