21264206 has 4 divisors (see below), whose sum is σ = 31896312. Its totient is φ = 10632102.

The previous prime is 21264203. The next prime is 21264209. The reversal of 21264206 is 60246212.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21264203) and next prime (21264209).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21264203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5316050 + ... + 5316053.

It is an arithmetic number, because the mean of its divisors is an integer number (7974078).

Almost surely, 2^21264206 is an apocalyptic number.

21264206 is a deficient number, since it is larger than the sum of its proper divisors (10632106).

21264206 is a wasteful number, since it uses less digits than its factorization.

21264206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10632105.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 21264206 is about 4611.3128282518. The cubic root of 21264206 is about 277.0446217437.

The spelling of 21264206 in words is "twenty-one million, two hundred sixty-four thousand, two hundred six".