21254405213 has 4 divisors (see below), whose sum is σ = 21257381280. Its totient is φ = 21251429148.

The previous prime is 21254405209. The next prime is 21254405219. The reversal of 21254405213 is 31250445212.

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 21254405213 - 2² = 21254405209 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 (21254405219) 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, 1477295 + ... + 1491612.

It is an arithmetic number, because the mean of its divisors is an integer number (5314345320).

Almost surely, 2^21254405213 is an apocalyptic number.

It is an amenable number.

21254405213 is a deficient number, since it is larger than the sum of its proper divisors (2976067).

21254405213 is an equidigital number, since it uses as much as digits as its factorization.

21254405213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2976066.

The product of its (nonzero) digits is 9600, while the sum is 29.

The spelling of 21254405213 in words is "twenty-one billion, two hundred fifty-four million, four hundred five thousand, two hundred thirteen".