21399301 has 16 divisors (see below), whose sum is σ = 28085760. Its totient is φ = 15796080.

The previous prime is 21399299. The next prime is 21399307. The reversal of 21399301 is 10399312.

It is a cyclic number.

It is not a de Polignac number, because 21399301 - 2¹ = 21399299 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 21399301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21399307) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5851 + ... + 8776.

It is an arithmetic number, because the mean of its divisors is an integer number (1755360).

Almost surely, 2^21399301 is an apocalyptic number.

21399301 is the 2926-th heptagonal number.

It is an amenable number.

21399301 is a deficient number, since it is larger than the sum of its proper divisors (6686459).

21399301 is a wasteful number, since it uses less digits than its factorization.

21399301 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14664.

The product of its (nonzero) digits is 1458, while the sum is 28.

The square root of 21399301 is about 4625.9378508579. The cubic root of 21399301 is about 277.6300869939.

The spelling of 21399301 in words is "twenty-one million, three hundred ninety-nine thousand, three hundred one".