21201969 has 8 divisors (see below), whose sum is σ = 28561120. Its totient is φ = 13988736.

The previous prime is 21201937. The next prime is 21201979. The reversal of 21201969 is 96910212.

It is a happy number.

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

It is not a de Polignac number, because 21201969 - 2⁵ = 21201937 is a prime.

It is a super-2 number, since 2×21201969² = 899046978953922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21201919) 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, 36139 + ... + 36720.

It is an arithmetic number, because the mean of its divisors is an integer number (3570140).

Almost surely, 2^21201969 is an apocalyptic number.

It is an amenable number.

21201969 is a deficient number, since it is larger than the sum of its proper divisors (7359151).

21201969 is an equidigital number, since it uses as much as digits as its factorization.

21201969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72959.

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 21201969 is about 4604.5595880605. The cubic root of 21201969 is about 276.7740688798.

The spelling of 21201969 in words is "twenty-one million, two hundred one thousand, nine hundred sixty-nine".