21950065 has 16 divisors (see below), whose sum is σ = 27524160. Its totient is φ = 16787520.

The previous prime is 21950053. The next prime is 21950099. The reversal of 21950065 is 56005912.

21950065 = T₁₆₀ + T₁₆₁ + ... + T₅₁₃.

It is not a de Polignac number, because 21950065 - 2⁹ = 21949553 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9910 + ... + 11920.

It is an arithmetic number, because the mean of its divisors is an integer number (1720260).

Almost surely, 2^21950065 is an apocalyptic number.

It is an amenable number.

21950065 is a deficient number, since it is larger than the sum of its proper divisors (5574095).

21950065 is a wasteful number, since it uses less digits than its factorization.

21950065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2112.

The product of its (nonzero) digits is 2700, while the sum is 28.

The square root of 21950065 is about 4685.0896469545. The cubic root of 21950065 is about 279.9917727174.

Adding to 21950065 its reverse (56005912), we get a palindrome (77955977).

The spelling of 21950065 in words is "twenty-one million, nine hundred fifty thousand, sixty-five".