21950863 has 4 divisors (see below), whose sum is σ = 23946408. Its totient is φ = 19955320.

The previous prime is 21950849. The next prime is 21950897. The reversal of 21950863 is 36805912.

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

It is a de Polignac number, because none of the positive numbers 2^k-21950863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21950843) 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, 997756 + ... + 997777.

It is an arithmetic number, because the mean of its divisors is an integer number (5986602).

Almost surely, 2^21950863 is an apocalyptic number.

21950863 is a deficient number, since it is larger than the sum of its proper divisors (1995545).

21950863 is a wasteful number, since it uses less digits than its factorization.

21950863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1995544.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 21950863 is about 4685.1748099724. The cubic root of 21950863 is about 279.9951657329.

The spelling of 21950863 in words is "twenty-one million, nine hundred fifty thousand, eight hundred sixty-three".