21369601 has 8 divisors (see below), whose sum is σ = 23347008. Its totient is φ = 19398000.

The previous prime is 21369589. The next prime is 21369617. The reversal of 21369601 is 10696312.

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 21369601 - 2⁷ = 21369473 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21369601.

It is not an unprimeable number, because it can be changed into a prime (21360601) 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, 10756 + ... + 12586.

It is an arithmetic number, because the mean of its divisors is an integer number (2918376).

Almost surely, 2^21369601 is an apocalyptic number.

It is an amenable number.

21369601 is a deficient number, since it is larger than the sum of its proper divisors (1977407).

21369601 is a wasteful number, since it uses less digits than its factorization.

21369601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2903.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 21369601 is about 4622.7265763832. The cubic root of 21369601 is about 277.5015869833.

Subtracting from 21369601 its reverse (10696312), we obtain a square (10673289 = 3267²).

The spelling of 21369601 in words is "twenty-one million, three hundred sixty-nine thousand, six hundred one".