21823801 has 4 divisors (see below), whose sum is σ = 23107572. Its totient is φ = 20540032.

The previous prime is 21823793. The next prime is 21823811. The reversal of 21823801 is 10832812.

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

It can be written as a sum of positive squares in 2 ways, for example, as 20466576 + 1357225 = 4524^2 + 1165^2 .

It is a cyclic number.

It is not a de Polignac number, because 21823801 - 2³ = 21823793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21823811) 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, 641860 + ... + 641893.

It is an arithmetic number, because the mean of its divisors is an integer number (5776893).

Almost surely, 2^21823801 is an apocalyptic number.

It is an amenable number.

21823801 is a deficient number, since it is larger than the sum of its proper divisors (1283771).

21823801 is a wasteful number, since it uses less digits than its factorization.

21823801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1283770.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 21823801 is about 4671.5951237238. The cubic root of 21823801 is about 279.4538717167.

The spelling of 21823801 in words is "twenty-one million, eight hundred twenty-three thousand, eight hundred one".