21346253 has 4 divisors (see below), whose sum is σ = 22469760. Its totient is φ = 20222748.

The previous prime is 21346223. The next prime is 21346261. The reversal of 21346253 is 35264312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21346253 - 2⁸ = 21345997 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 (21346223) 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, 561725 + ... + 561762.

It is an arithmetic number, because the mean of its divisors is an integer number (5617440).

Almost surely, 2^21346253 is an apocalyptic number.

It is an amenable number.

21346253 is a deficient number, since it is larger than the sum of its proper divisors (1123507).

21346253 is a wasteful number, since it uses less digits than its factorization.

21346253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1123506.

The product of its digits is 4320, while the sum is 26.

The square root of 21346253 is about 4620.2005367733. The cubic root of 21346253 is about 277.4004859203.

The spelling of 21346253 in words is "twenty-one million, three hundred forty-six thousand, two hundred fifty-three".