21620450 has 24 divisors (see below), whose sum is σ = 40453140. Its totient is φ = 8596800.

The previous prime is 21620419. The next prime is 21620453. The reversal of 21620450 is 5402612.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 543169 + 21077281 = 737^2 + 4591^2 .

It is not an unprimeable number, because it can be changed into a prime (21620453) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 7856 + ... + 10244.

Almost surely, 2^21620450 is an apocalyptic number.

21620450 is a deficient number, since it is larger than the sum of its proper divisors (18832690).

21620450 is a wasteful number, since it uses less digits than its factorization.

21620450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2582 (or 2577 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 21620450 is about 4649.7795646676. The cubic root of 21620450 is about 278.5831916388.

The spelling of 21620450 in words is "twenty-one million, six hundred twenty thousand, four hundred fifty".