21350865 has 8 divisors (see below), whose sum is σ = 34161408. Its totient is φ = 11387120.

The previous prime is 21350863. The next prime is 21350867. The reversal of 21350865 is 56805312.

It is an interprime number because it is at equal distance from previous prime (21350863) and next prime (21350867).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21350865 - 2¹ = 21350863 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21350863) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 711681 + ... + 711710.

It is an arithmetic number, because the mean of its divisors is an integer number (4270176).

Almost surely, 2^21350865 is an apocalyptic number.

It is an amenable number.

21350865 is a deficient number, since it is larger than the sum of its proper divisors (12810543).

21350865 is a wasteful number, since it uses less digits than its factorization.

21350865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1423399.

The product of its (nonzero) digits is 7200, while the sum is 30.

The square root of 21350865 is about 4620.6996223516. The cubic root of 21350865 is about 277.4204625553.

The spelling of 21350865 in words is "twenty-one million, three hundred fifty thousand, eight hundred sixty-five".