21269901 has 8 divisors (see below), whose sum is σ = 28381824. Its totient is φ = 14168960.

The previous prime is 21269879. The next prime is 21269903. The reversal of 21269901 is 10996212.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21269901 - 2⁶ = 21269837 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21269903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4540 + ... + 7946.

It is an arithmetic number, because the mean of its divisors is an integer number (3547728).

Almost surely, 2^21269901 is an apocalyptic number.

It is an amenable number.

21269901 is a deficient number, since it is larger than the sum of its proper divisors (7111923).

21269901 is a wasteful number, since it uses less digits than its factorization.

21269901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5491.

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

The square root of 21269901 is about 4611.9302900196. The cubic root of 21269901 is about 277.0693523212.

The spelling of 21269901 in words is "twenty-one million, two hundred sixty-nine thousand, nine hundred one".