20526865 has 4 divisors (see below), whose sum is σ = 24632244. Its totient is φ = 16421488.

The previous prime is 20526841. The next prime is 20526889. The reversal of 20526865 is 56862502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56862502 = 2 ⋅28431251.

It is an interprime number because it is at equal distance from previous prime (20526841) and next prime (20526889).

It can be written as a sum of positive squares in 2 ways, for example, as 11723776 + 8803089 = 3424^2 + 2967^2 .

It is a cyclic number.

It is not a de Polignac number, because 20526865 - 2²¹ = 18429713 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20526865.

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, 2052682 + ... + 2052691.

It is an arithmetic number, because the mean of its divisors is an integer number (6158061).

Almost surely, 2^20526865 is an apocalyptic number.

It is an amenable number.

20526865 is a deficient number, since it is larger than the sum of its proper divisors (4105379).

20526865 is an equidigital number, since it uses as much as digits as its factorization.

20526865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4105378.

The product of its (nonzero) digits is 28800, while the sum is 34.

The square root of 20526865 is about 4530.6583406830. The cubic root of 20526865 is about 273.8046852519.

The spelling of 20526865 in words is "twenty million, five hundred twenty-six thousand, eight hundred sixty-five".