21975465 has 16 divisors (see below), whose sum is σ = 36690048. Its totient is φ = 11210496.

The previous prime is 21975463. The next prime is 21975487. The reversal of 21975465 is 56457912.

It is not a de Polignac number, because 21975465 - 2¹ = 21975463 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21975463) 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 15 ways as a sum of consecutive naturals, for example, 31504 + ... + 32193.

It is an arithmetic number, because the mean of its divisors is an integer number (2293128).

Almost surely, 2^21975465 is an apocalyptic number.

It is an amenable number.

21975465 is a deficient number, since it is larger than the sum of its proper divisors (14714583).

21975465 is a wasteful number, since it uses less digits than its factorization.

21975465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63728.

The product of its digits is 75600, while the sum is 39.

The square root of 21975465 is about 4687.7995904262. The cubic root of 21975465 is about 280.0997306301.

The spelling of 21975465 in words is "twenty-one million, nine hundred seventy-five thousand, four hundred sixty-five".