21628301 has 4 divisors (see below), whose sum is σ = 22900572. Its totient is φ = 20356032.

The previous prime is 21628283. The next prime is 21628339. The reversal of 21628301 is 10382612.

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 7150276 + 14478025 = 2674^2 + 3805^2 .

It is a cyclic number.

It is not a de Polignac number, because 21628301 - 2⁶ = 21628237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21628351) 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, 636110 + ... + 636143.

It is an arithmetic number, because the mean of its divisors is an integer number (5725143).

Almost surely, 2^21628301 is an apocalyptic number.

It is an amenable number.

21628301 is a deficient number, since it is larger than the sum of its proper divisors (1272271).

21628301 is a wasteful number, since it uses less digits than its factorization.

21628301 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1272270.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 21628301 is about 4650.6237216098. The cubic root of 21628301 is about 278.6169080500.

The spelling of 21628301 in words is "twenty-one million, six hundred twenty-eight thousand, three hundred one".