21954001 has 4 divisors (see below), whose sum is σ = 22050100. Its totient is φ = 21857904.

The previous prime is 21953999. The next prime is 21954011. The reversal of 21954001 is 10045912.

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 12960000 + 8994001 = 3600^2 + 2999^2 .

It is a cyclic number.

It is not a de Polignac number, because 21954001 - 2¹ = 21953999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21954011) 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, 47706 + ... + 48163.

It is an arithmetic number, because the mean of its divisors is an integer number (5512525).

Almost surely, 2^21954001 is an apocalyptic number.

It is an amenable number.

21954001 is a deficient number, since it is larger than the sum of its proper divisors (96099).

21954001 is an equidigital number, since it uses as much as digits as its factorization.

21954001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96098.

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 21954001 is about 4685.5096841219. The cubic root of 21954001 is about 280.0085073946.

Adding to 21954001 its reverse (10045912), we get a palindrome (31999913).

The spelling of 21954001 in words is "twenty-one million, nine hundred fifty-four thousand, one".