21445064 has 16 divisors (see below), whose sum is σ = 40761420. Its totient is φ = 10575360.

The previous prime is 21445037. The next prime is 21445111. The reversal of 21445064 is 46054412.

It can be written as a sum of positive squares in 2 ways, for example, as 18852964 + 2592100 = 4342^2 + 1610^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17777 + ... + 18944.

Almost surely, 2^21445064 is an apocalyptic number.

It is an amenable number.

21445064 is a deficient number, since it is larger than the sum of its proper divisors (19316356).

21445064 is a wasteful number, since it uses less digits than its factorization.

21445064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36800 (or 36796 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 21445064 is about 4630.8815575439. The cubic root of 21445064 is about 277.8278526377.

Adding to 21445064 its reverse (46054412), we get a palindrome (67499476).

The spelling of 21445064 in words is "twenty-one million, four hundred forty-five thousand, sixty-four".