21626867 has 4 divisors (see below), whose sum is σ = 21729576. Its totient is φ = 21524160.

The previous prime is 21626819. The next prime is 21626881. The reversal of 21626867 is 76862612.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21626867 - 2¹² = 21622771 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 21626867.

It is not an unprimeable number, because it can be changed into a prime (21626887) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51038 + ... + 51459.

It is an arithmetic number, because the mean of its divisors is an integer number (5432394).

Almost surely, 2^21626867 is an apocalyptic number.

21626867 is a deficient number, since it is larger than the sum of its proper divisors (102709).

21626867 is a wasteful number, since it uses less digits than its factorization.

21626867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102708.

The product of its digits is 48384, while the sum is 38.

The square root of 21626867 is about 4650.4695461856. The cubic root of 21626867 is about 278.6107502929.

The spelling of 21626867 in words is "twenty-one million, six hundred twenty-six thousand, eight hundred sixty-seven".