21987050 has 24 divisors (see below), whose sum is σ = 41672556. Its totient is φ = 8627840.

The previous prime is 21987041. The next prime is 21987059. The reversal of 21987050 is 5078912.

It is an interprime number because it is at equal distance from previous prime (21987041) and next prime (21987059).

It can be written as a sum of positive squares in 6 ways, for example, as 17581249 + 4405801 = 4193^2 + 2099^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21986998 and 21987016.

It is not an unprimeable number, because it can be changed into a prime (21987059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1499 + ... + 6798.

Almost surely, 2^21987050 is an apocalyptic number.

21987050 is a deficient number, since it is larger than the sum of its proper divisors (19685506).

21987050 is a wasteful number, since it uses less digits than its factorization.

21987050 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8362 (or 8357 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 32.

The square root of 21987050 is about 4689.0350819758. The cubic root of 21987050 is about 280.1489428663.

The spelling of 21987050 in words is "twenty-one million, nine hundred eighty-seven thousand, fifty".