21878150 has 48 divisors (see below), whose sum is σ = 49255776. Its totient is φ = 7057920.

The previous prime is 21878149. The next prime is 21878243. The reversal of 21878150 is 5187812.

It is a happy number.

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, 4112 + ... + 7788.

It is an arithmetic number, because the mean of its divisors is an integer number (1026162).

Almost surely, 2^21878150 is an apocalyptic number.

21878150 is an abundant number, since it is smaller than the sum of its proper divisors (27377626).

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

21878150 is a wasteful number, since it uses less digits than its factorization.

21878150 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3713 (or 3708 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 32.

The square root of 21878150 is about 4677.4084705101. The cubic root of 21878150 is about 279.6856591433.

The spelling of 21878150 in words is "twenty-one million, eight hundred seventy-eight thousand, one hundred fifty".